Dissertations / Theses on the topic 'Low temperature photoluminescence'

Thesis (M.S.)--Dept. of Physics. University of Missouri--Kansas City, 2004.
"A thesis in physics." Typescript. Advisor: Michael B. Kruger. Vita. Title from "catalog record" of the print edition Description based on contents viewed Feb. 28, 2006. Includes bibliographical references (leaves 32-33 ). Online version of the print edition.

Measurements of the photoluminescence emission spectra of 99.999 % purity gold, 99.9999 % purity copper, polycrystalline PbMo6S8 and single crystal YBCO were made for λex = 488 nm as a function of temperature (72 K < T < 300 K), time (t < 12 hours), excitation power (P < 120 mW) and position on the sample using a high sensitivity instrument which was designed, commissioned and calibrated for this study. We present the first measurements of the photoluminescence emission spectra of gold and copper as a function of temperature which show peak photoluminescence emission intensity increasing by approximately a factor of two for gold and a factor of five for copper between 300 K and 79 K. Full width half maximum (FWHM) and peak photoluminescence emission wavelength showed no dependence upon temperature. The spectra compare well to published data and data modelled using theories presented in the literature. Variable temperature measurements on the superconductors PbMo6S8 and YBCO in their normal state show peak photoluminescence intensity increasing by a factor of 1.5 between 300 K and 80 K for PbMo6S8 and a factor of 2 between 300 K and 131 K for YBCO. A decrease in FWHM of 20 - 30 nm is observed with no change in peak photoluminescence wavelength. Measurements for 99.99 % purity single crystal niobium, polycrystalline SnMo6S8 and single crystal DyBCO superconductors are also presented, however, these samples exhibited problems with oxidation, impurities or damage to the sample surface. Two interesting features which remain unexplained from this work include a variation in photoluminescence emission intensity over < 12 hours with a period of ~400 minutes for gold and copper and a continuous decrease in intensity for niobium, SnMo6S8 and YBCO and an increase in photoluminescence emission intensity by a factor of 4 at low temperatures in PbMo6S8, SnMo6S8 and YBCO.

The work deals with low-temperature photoluminescence and deformation luminescence (mechanolu-minescence) of a composite material based on fine disperse powder of phosphor SrAl2O4:(Eu2+, Dy3+) and photopolymerizing resin that is transparent in the visible region. It has been shown that at the low tem-perature (T=15÷200 K) the photoluminescence spectrum of SrAl2O4:(Eu2+, Dy3+) displays two wide, partial-ly overlapping bands with the maxima at λ1max517 nm and λ2max446 nm. The short-wave luminescence band (λ2max446 nm) has been found to undergo temperature quenching and to completely decay at T200 K. A mechanism of mechanoluminescence excitation has been suggested. It has been shown that the com-posite material exhibits high sensitivity to mechanical action. When you are citing the document, use the following link http://essuir.sumdu.edu.ua/handle/123456789/35389

When studying quantum dots one of the most important properties is the size of the band gap, and thus also their physical dimensions. We investigated these properties for silicon quantum dots created by means of plasma-enhanced chemical vapour deposition and annealing. To determine the band gap size we measured photoluminescence for ten dierent samples and to determine the physical dimensions we used an atomic force microscope. The photoluminescence measurements indicated that the intensity of the emitted photons varied across the samples, but did not indicate any shift in peak wavelength between samples nor any time-dependence of the luminescence. The peak wavelength was in the order of 600 to 620 nm, corresponding to a band gap of 2.0 to 2.1 eV and a physical size of approximately 3 nm. The AFM scans revealed densely packed quantum dots, where few single objects could be distinguished. In order to be able to perform a better statistical analysis, eorts would have to be taken to separate the quantum dots.

Optical studies of heavily-doped GaAs:C grown at low temperature by molecular beam epitaxy were performed using room-temperature photoluminescence, infrared transmission, and Raman scattering measurements. The photoluminescence experiments show that in LT-GaAs:C films grown at temperatures below 400 °C, nonradiative recombination processes dominate and photoluminescence is quenched. When the growth temperature exceeds 400 °C, band-to-band photoluminescence emission appears. We conclude that the films change in character from LT-GaAs:C to normal GaAs:C once the growth temperature reaches 400 °C. Annealing, however, shows a different behavior. Once grown as LT-GaAs:C, this material retains its nonconducting nonluminescing LT characteristics even when annealed at 600 °C. The Raman-scattering measurements showed that the growth temperature and the doping concentration influence the position, broadening, and asymmetry of the longitudinal-optical phonon Raman line. We attribute these effects to changes in the concentration of interstitial carbon in the films. Also, the shift of the Raman line was used to estimate the concentration of arsenic-antisite defects in undoped LT-GaAs. The infrared transmission measurements on the carbon-doped material showed that only a fraction of the carbon atoms occupy arsenic sites, that this fraction increases as the growth temperature increases, and that it reaches about 100% once the growth temperature reaches 400 °C. The details of all these measurements are discussed. Infrared transmission and photoluminescence measurements were also carried out on heavily-doped GaAs:C films grown by molecular beam epitaxy at the standard 600 C temperature. The infrared results reveal, for dopings under 5 x 10⁹ cm⁻³, a linear relation between doping concentration and the integrated optical absorption of the carbon localized-vibrational-mode band. At higher dopings, the LVM integrated absorption saturates. Formation of C_As-C_As clusters is proposed as the mechanism of the saturation. The photoluminescence spectra were successfully analyzed with a simple model assuming thermalization of photoelectrons to the bottom of the conduction band and indirect-transition recombination with holes populating the degenerately doped valence band. The analysis yields the bandgap reduction and the Fermi-level-depth increase at high doping.
Ph. D.

Identification des types de recombinaison entre 2 et 300k dans les couches epaisses de gainas et gainp epitaxiees sur leur support respectif inp et gaas. Etude de l'origine de la luminescence et variation en fonction de l'epaisseur du taux de capture des porteurs de la barriere dans les puits quantiques ingaas/inp. Determination du coefficient d'interdiffusion de al et ga aux interfaces dans les puits quantiques gaas/gaalas

A close relation between structural and optical properties of any semiconductor material does exist. An adequate knowledge and understanding of this relationship is necessary for fabrication of devices with desired optical properties. The structural quality and hence the optical properties can be influenced by the growth method and the substrate used. The aim of this work was to investigate the change in optical properties caused by growth techniques and substrate modification. To study the influence of growth technique on optical properties, ZnO nanostructures were grown using atmospheric pressure metal organic chemical vapor deposition (APMOCVD) and chemical bath deposition (CBD) technique. The structural and optical investigations were performed using scanning electron microscopy (SEM) and micro photoluminescence (μ-PL), respectively. The results revealed that the grown structures were in the shape of nano-rods with slightly different shapes. Optical investigation revealed that low temperature PL spectrum for both the samples was dominated by neutral donor bound excitons emission and it tends to be replaced by free exciton (FX) emission in the temperature range of 60-140K. Both excitonic emissions show a typical red-shift with increase in temperature but with a different temperature dynamics for both the sample and this is due to difference in exciton-phonon interaction because of the different sizes of nano-rods. Defect level emission (DLE) is negligible in both the sample at low temperature but it increased linearly in intensity after 130 K up to the room temperature.Modification in substrate can also play a significant role on structural and optical properties of the material. Specially variation in the miscut angle of substrate can help to control the lateral sizes of the Nanostructures and thus can help to obtain better structural andoptical quality. Also optical quality is a key requirement for making blue and ultraviolet LEDs. Therefore, ZnO Nanostructures were grown on SiC on-axis and off-axis substrates having different off-cut angles. Morphological investigation revealed thatgrown structures are epitaxial for the case when substrate off-cut angle is higher and deposition rate is low. Low temperature PL spectrum of all the samples was dominated by neutral donor bound excitons and free exciton emission become dominant at 100 K for all the samples which completely eliminate the neutral donor bound excitonic emission at 160K. Two electron satellite of the neutral donor bound excitons and LO phonons of excitonic features are also present. A typical red-shift in excitonic features was evident in temperature dependence measurement. Red-shift behavior of free exciton for all the samples was treated by applying Varshni empirical expression and several important parameter, such as, the Debye temperature and the band gap energy value was extracted. Thermal quenching behavior was also observed and treated by thermal quenching expression and value of the activation energy for non-radiative channel was extracted. The results that are obtained demonstrate a significant contribution in the fields of ZnO based nano-optoelectronics and nano-electronics.

Ce travail porte sur la caractérisation structurale et optique d'échantillons de SiC. Les échantillons étudiés ont été répartis en trois groupes : des échantillons massifs, des couches épitaxiales épaisses et enfin des couches minces. La croissance des échantillons massifs a été réalisée avec la technique CF-PVT, utilisant une géométrie « d'étranglement ». L'objectif était de filtrer les défauts afin de créer des germes de 3C de haute pureté. La croissance de des couches épaisses par sublimation avait comme objectif la maitrise d'un dopage résiduel faible de type n et p pour des applications composants. Enfin, dans le but de réaliser des composants de type LED blanche des impuretés Ga ont été introduites dans des couches minces épitaxiées par VLS afin de créer des échantillons fortement dopé de type p. Tous ces échantillons ont été étudiés par photoluminescence, micro-Raman, SIMS et microscopie électronique à transmission. Il a été possible de déterminer la concentration d'impuretés et d'identifier le caractère n ou p de ces échantillons. L'analyse des échantillons a été faite en utilisant à la fois l'observation des défauts structurels et les informations obtenues à partir des techniques de caractérisation optique. Nous avons pu obtenir des informations sur les paramètres physiques de 3C-SiC, comme l'énergie de liaison de Ga et Al, la structure fine des excitons liés à l'Al et celle des paires donneurs accepteurs Al-N et Ga-N. Enfin l'apparition d'un nouveau défaut de structure appelée le « fourfold twin » a été observée
The main topic of this thesis is the structural and optical characterization of SiC samples. The samples were divided in three groups: bulk, thick and thin epilayers. The bulk samples were grown with the CF-PVT technique and used a modified crystal holder geometry. The objective was to filter the defects to and create high purity and quality seeds of 3C-SiC. The thick epilayers were grown with the sublimation epitaxy technique, trying to demonstrate the creation of low impurity n and p type layers for device applications. Finally the thin epilayers were grown with the vapour-liquid-solid technique and doped with Ga impurities in an effort to create either heavily p-type doped samples and components for white LED applications. The samples were studied with low temperature photoluminescence, micro-Raman, SIMS and transmission electron microscopy. With the help of these techniques it was possible to determine the impurity concentration and identif y the n or p character of these samples. A qualitative analysis of the quality of the samples was done using both the observation of the structural defects and the information from the optical characterization techniques. We were able to acquire information about physical parameters of 3C-SiC like the binding energy of Ga and Al, the Al bound exciton fine structure and the Al-N and Ga-N donor acceptor pair fine structure. The appearance of a new structural defect called the fourfold twin was observed and presented

Une des limitations dans l'exploitation généralisée de l'énergie photonique principalement d'origine solaireest la limitation du rendement des cellules photovoltaiques (pv) qui ne peut être améliorée aujourd’hui au planindustriel, qu’en utilisant des matériaux chers, rares voire dangereux. Le matériau le plus abondant le moinstoxique à la fabrication et au recyclage, qui aujourd’hui est le moins cher et le mieux maîtriséindustriellement est le silicium, mais la part du spectre lumineux convertible en électricité reste incomplètece qui pour conséquence de limiter le rendement.L’introduction de la nanotechnologie photonique permet par un effet de photoconversion multi-étage horsbandgap d'augmenter le rendement de photoconversion en élargissant le spectre photoconvertible du silicumnatif. La nano-unité opérationnelle du silicium cristallin dans ce cas, est nommée "Segton" qui est unevariante de bilacune organisée en couche enterrée et située à l'interface créé artificiellement entre du siliciumamorphe et du silicium cristallin.Ces travaux font le point sur les démonstrateurs réalisés de cellules à photoconversion géante en particuliersur les derniers moyens technologiques pré-industriels exploités pour ces fabrications notamment a ceux misen œuvre avec différents laboratoires.La thèse propose de nouveaux moyens de caractérisation adaptés à la photoconversion en utilisant laphotoluminescence à basse température.Enfin, un bilan est détaillé sur les activités de simulation, de fabrication et de caractérisation se terminant parune présentation prospective de futures productions industrielles
One of the limitations to the widespread use of photonic energy is the limited efficiency of photovoltaic (PV) cells, which can only be improved industrially today by using expensive, rare and toxic materials or fragile devices. Silicon is the most abundant material, the least toxic to manufacture and recycle. It is also the cheapest and the best mastered industrially. However, the proportion of the light spectrum that can be converted into electricity remains incomplete, which limits its efficiency. The introduction of photonic nanotechnology has made it possible to increase photoconversion efficiency by broadening the photoconvertible spectrum of native silicon and by using a multistage photoconversion effect outside the band gap. The operational nano-unit of crystalline silicon in this case is the "Segton", which is avariant of the divacancy organized as a buried layer and located at the artificially created interface between amorphous and crystalline silicon. This work provides an update on the demonstrators of giânt photoconversion cells, and in particular on the latest pre-industrial technological resources used for this type of production. This was implemented incollaboration with various laboratories. This thesis proposes new characterization methods adapted to photoconversion using the low-temperature photoluminescence spectra in order to detect the good generation of divacancies due to the implementation steps during the fabrication. Finally, the simulation, the manufacturing and the characterization activities are reviewed in detail, ending with a prospective to future industrial production

When studying quantum dots one of the most important properties is the size of the band gap, and thus also their physical dimensions. We investigated these properties for silicon quantum dots created by means of plasma-enhanced chemical vapour deposition and annealing. To determine the band gap size we measured photoluminescence for ten dierent samples and to determine the physical dimensions we used an atomic force microscope. The photoluminescence measurements indicated that the intensity of the emitted photons varied across the samples, but did not indicate any shift in peak wavelength between samples nor any time-dependence of the luminescence. The peak wavelength was in the order of 600 to 620 nm, corresponding to a band gap of 2.0 to 2.1 eV and a physical size of approximately 3 nm. The AFM scans revealed densely packed quantum dots, where few single objects could be distinguished. In order to be able to perform a better statistical analysis, eorts would have to be taken to separate the quantum dots.

碩士
國立清華大學
材料科學工程學系
91
During last few years much effort has been made on the research of nanostructures novel, especially Si-based luminescent nanostructures due to their optical properties. However, the luminescence mechanisms for most of these luminescent materials are not clear and definitive till now. The present work involves the fabrication of oxygen-containing Si nanoparticles (OCSNs) by a thermal evaporation technique and measurement of photoluminescence (PL). The possible mechanism responsible for the PL is discussed. The SiOx nanoparticles were prepared in a mixed atmosphere of argon and oxygen. The effect of Si weight on the formation of the nanocrystals and the PL properties is studied in this thesis. The SiOx nanoparticles prepared with lower oxygen content exhibit lower PL intensity, while a strong blue-green PL is observed from those prepared with higher oxygen contents. It is interesting to note that there is a critical oxygen-content in the SiOx nanoparticles emits PL light varying from blue-white to orange. The mechanism of blue-light emission from SiOx nanoparticles is also discussed. In another experiment, it is found that the PL properties have been changed after depositing the SiOx nanoparticleson the Si substrate. The structure and PL behavior of these SiOx films are also discussed on the basis of low angle XRD and FESEM analyes. The last part of this thesis is focused on the low-temperature PL behavior of isolated SiOx nanoparticles and SiOx films. The PL intensity is increased after the low temperature PL test. The intensity transition temperatures for SiOx nanoparticles and SiOx films have also been measured. The low temperature PL behaviors of the SiOx nanoparticles and SiOx are discussed in terms of the changes of the SiOx nanostructures. After low temperature PL test, it is interesting to note that the structures of SiOx films have been changed. This change in structure may be responsible for higher PL intensity. Key words：SiOx nanoparticles, SiOx films, PL, XRD, TEM, FESEM, Low-temperature PL

碩士
大葉大學
電機工程學系
101
The epitaxial growth ZnO films were deposited on Si substrates by rf magnetron sputtering with substrate temperature below 300 ℃. The growth of thin films was performed at a pressure of 40 mtorr Ar and O2 with a sputtering power of 100 W. The deposited samples were put into a quartz tube furnace to anneal with various atmospheric. The crystallinity and crystal direction of the ZnO films were investigated by the X-ray diffractometry. Scanning electron microscopy (SEM) was utilized to study the surface morphology of the ZnO films. The photoluminescence (PL) spectra of the deposited films were measured to analyze the band gaps. In this thesis, the gap states of the ZnO films grown on different condition were explored. According to the experimental results, the strongest UV emission intensity was obtained at the sample with 900 ℃ post-annealing in the nitrogen, and the strongest green emission intensity was obtained at the sample with 900 ℃ post-annealing in the oxygen ambient.

碩士
國立交通大學
電子物理系所
101
The species and concentration of trace III-V impurity in silicon wafers are determined by photoluminescence (PL). At low temperature and low excitation conditions, the emission of free exciton (FE) and impurity-bound exciton (BE) could be clearly observed. In particularly, the intensity ratio between BE and FE increases with increasing impurity concentration, having a correlation close to linear dependence. The intensity ratio for impurity concentration between 1011~1014 cm-3 have been measured using calibration samples, by which the impurity species and concentration in silicon wafers can be determined. In the second part, the Mn concentration in GaN is determined by reflectance spectra, and the impact of Mn on bandgap is measured by PL. First, the increasing FE energy with the increasing Mn concentration is observed by PL, indicating the p-d exchange interaction plays a very important role in this material. Then, the intra-atomic absorption of Mn3+ can be measured by reflectance spectra, the concentration of Mn3+ has a linear dependence on the Mn incorporation.

Laser processing is now regarded as a promising tool to reduce the cost and complexity of fabricating the formation of localized contacts between heavily doped silicon and metal, features which have become an important element in high efficiency silicon solar cells, such as a passivated emitter and rear cell (PERC) and an interdigitated back contact cell (IBC). However, characterization of localized features with conventional PV characterization tools is challenging, mainly due to the limitations of spatial resolution. This thesis develops and applies novel characterization methods to these localized features using low temperature micro-photoluminescence spectroscopy (μ-PLS). This technique demonstrates that localized features, even single laser pulse processed regions typically tens of micrometres in scale, can be investigated directly without the need for specific sample structures and their electronic properties can be mapped spatially in the sub-micrometre regime. Utilizing the sub-micron precision of these measurements, the laser-induced crystallographic damages were investigated at various positions within the laser-processed region, particularly at specific points such as the boundary/edge of processed and unprocessed regions. It was found that the edge, or pulse overlapped regions, were significantly more defective than the centre region. The impact of laser parameters, such as laser pulse fluence and number of repeat pulses, on laser-induced damage was also analysed. Significantly different levels of defect-related PL signals were observed after laser processing of the two different substrate surface conditions. This suggests that wafer surface preparation can be an important factor impacting on the quality of laser-processed silicon. The doping profiles of thermally boron-diffused silicon samples, which have Gaussian function type doping profiles, can be estimated from the measured PL spectra alone. The wavelength of the doping-related PL peak (doping peak) has a reliable and simple linear relationship with the surface dopant density on a semi-log plot. The PL intensity of the doping peak also shows a linear relationship with the doping depth metric (depth factor), but only after considering the reduction of PL intensity due to enhanced incomplete dopant ionization at low temperature. Doping profiles can be easily reconstructed based on these two linear relationships and their vi accuracy was verified by comparisons with existing doping profiles (via ECV profiling). Mapping of the surface dopant density and the depth factor of micron-scale locally diffused features was undertaken using 2-D mapping with μ-PLS measurements at 2 μm spatial resolution. This method was also applied to 532 nm laser-doped silicon to show its effectiveness on locally laser-doped features. The doping profiles of laser-doped silicon were also successfully estimated from PL spectra measurements alone, along with 2-D maps of the surface dopant density and the depth factor of the laser-doped silicon. In addition, the impact of temporal pulse parameters, such as pulse duration and temporal pulse shapes, on the doping profiles and recombination properties of laser-doped silicon were investigated. By correlating defect-related PL band counts with the quantified recombination parameters determined by the luminescence-coupled numerical device simulations, it was shown that μ-PLS measurements are able to perform quantitative measurements of recombination properties. The last chapter of this thesis demonstrates an application of an advanced laser doping process using a stack of intrinsic amorphous silicon (Si:H(i)) and boron-doped amorphous silicon (a-Si:B). The results showed that this stack is able to provide excellent surface passivation as well as a sufficient amount of dopant source for laser doping. The method presented in this thesis is a very effective, simple and rapid characterization for analysing localized features, in particular spatially inhomogeneous laser-processed features on the micron-scale. This method enables the observation of the variation in properties within localized features which is not possible using conventional methods. It allows for a more in-depth study of laser processing and promotes further development of laser technologies for high efficiency cell fabrication.

Layered transition metal dichalcogenides (TMDCs) host a variety of strongly bound exciton complexes that control the optical properties in these materials. Apart from spin and valley, layer index provides an additional degree of freedom in a few-layer-thick lm. While in the 1H monolayer TMD inversion symmetry is broken, and the reflection symmetry is maintained but, in the bilayer, it is reversed. Trions are excitonic species with a positive or negative charge, and thus, unlike neutral excitons, the flow of trions can generate a net detectable charge current. Trions under favourable doping conditions can be created in a coherent manner using resonant excitation. The neutral biexciton (bound state of two excitons) can assemble further to create a charged state with another electron or hole. Generally, in W-based TMDs these ve-particle quinton states dominate the population density and this can also be engineered to produce photocurrent at cryogenic temperature. In the firrst work, we show that in a few-layer TMDC lm, the wave functions of the conduction and valence-band-edge states contributing to the K(K0) valley are spatially con ned in the alternate layers - giving rise to direct (quasi-)intralayer bright exciton and lower-energy interlayer dark excitons. Depending on the spin and valley con figuration, the bright-exciton state is further found to be a coherent superposition of two layer- induced states, one (E type) distributed in the even layers and the other (O type) in the odd layers. The intralayer nature of the bright exciton manifests as a relatively weak dependence of the exciton binding energy on the thickness of the few-layer lm, and the binding energy is maintained up to 50 meV in the bulk limit - which is an order of magnitude higher than conventional semiconductors. Fast Stokes energy transfer from the intralayer bright state to the interlayer dark states provides a clear signature in the layer-dependent broadening of the photoluminescence peak and plays a key role in the suppression of the photoluminescence intensity observed in TMDCs with thickness beyond a monolayer. In the second work, we show that bilayer WS2 exhibits a quantum con ned Stark effect (QCSE) that is linear with the applied out-of-plane electric field, in contrast to a quadratic one for a monolayer because of the contrasting symmetries between monolayer and bilayer. The interplay between the unique layer degree of freedom in the bilayer and the field-driven partial interconversion between intralayer and interlayer excitons generates a giant tunability of the exciton oscillator strength. This makes bilayer WS2 a promising candidate for an atomically thin, tuneable electro-absorption modulator at the exciton resonance, particularly when stacked on top of a graphene layer that provides an ultrafast nonradiative relaxation channel. By tweaking the biasing confi guration, we further show that the excitonic response can be largely tuned through electrostatic doping, by efficiently transferring the oscillator strength from neutral to charged exciton. In the third and fourth work, we demonstrate interlayer charge transport from top few-layer graphene to bottom monolayer graphene, mediated by a coherently formed trion state using a few-layer graphene/monolayer WS2/monolayer graphene vertical het- erojunction. This is achieved by using a resonant excitation and varying the sample temperature. The resulting change in the WS2 bandgap allows us to scan the excitation around the exciton-trion spectral overlap with high spectral resolution. By correlating the vertical photocurrent and in situ photoluminescence features at the heterojunction as a function of the spectral position of the excitation, we show that (1) trions are anoma- lously stable at the junction even up to 463 K due to enhanced doping, and (2) the photocurrent results from the ultrafast formation of a trion through exciton-trion coher- ent coupling, followed by its fast interlayer transport. Further, the resonant photocurrent thus generated can be effectively controlled by a back gate voltage applied through the incomplete screening of the bottom monolayer graphene, and the photocurrent strongly correlates with the gate dependent trion intensity, while the non-resonant photocurrent exhibits only a weak gate dependence. We estimate a sub-100 fs switching time of the device. In the final work, we have used the pulsed laser excitation to create the quinton states in monolayer WS2 while resonantly exciting the exciton and trion states at low temperature. Strong light absorption by the charged biexciton under spectral resonance, coupled with its charged nature, makes it intriguing for photodetection - an area that is hitherto unexplored. Using the high built-in vertical electric eld in an asymmetrically designed few-layer graphene encapsulated 1L-WS2 heterostructure, here we report, for the rst time, a large, highly nonlinear photocurrent arising from the strong absorption by two charged biexciton species under zero external bias (self-powered mode). Time- resolved measurement reveals that the photoresponse is ultra-fast, on the order of sub-5 ps. By using single- and two-color photoluminescence excitation spectroscopy, we show that the two biexcitonic peaks originate from bright-dark and bright-bright exciton-trion combinations. The possibility of electrical manipulation and detection of a charged exciton (trion) before its radiative recombination makes it promising for excitonic devices. The demon- stration of coherent formation, high stabilization, vertical transportation, and electrical detection of trions marks a step toward room-temperature trionics. Following the same the ve-particle charged quinton can also be efficiently generated and electrically de- tected. They can be used in electrical detection of constituting bright and dark states and quantum manipulation of the coupled spin-valley physics. Such innate nonlinearity in the photocurrent due to its biexcitonic origin, coupled with the ultra-fast response due to swift inter-layer charge transfer exempli fies the promise of manipulating many- body effects in monolayers. Also, the findings are prospective toward highly tunable, atomically thin, compact, and light on chip, re-confi gurable components and promising for several applications such as higher harmonics generation of the modulating signal, receiver design in microwave photonics and visible light communication, square-law cir- cuits, and also in nonlinear next generation optoelectronics.