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Journal articles on the topic 'Hyperfine decoherence'

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Published: 4 June 2021

Last updated: 31 January 2023

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1

MATHEW, AGILE, and MALAY K. NANDY. "DECOHERENCE STUDY OF ELECTRON SPIN STATES IN QUANTUM DOTS USING A SIMPLISTIC MODEL." Modern Physics Letters B 27, no. 16 (June 6, 2013): 1350119. http://dx.doi.org/10.1142/s0217984913501194.

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Using a simple model of central spin interacting with a spin bath, we study the decoherence of single electron spin states in quantum dots within one-, two- and three-dimensional nanostructure geometries. We consider a one-component hyperfine interaction term and express its strength as a smooth function of position vector. Decoherence measures are evaluated and plotted for various initial states, and we notice a decrease in decoherence time with the reduction of spin-bath dimension.

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2

Seigneur, Hubert Pascal, Gabriel Gonzalez, Michael Niklaus Leuenberger, and Winston Vaughan Schoenfeld. "Dynamics of Entanglement between a Quantum Dot Spin Qubit and a Photon Qubit inside a Semiconductor High-Q Nanocavity." Advances in Mathematical Physics 2010 (2010): 1–31. http://dx.doi.org/10.1155/2010/342915.

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We investigate in this paper the dynamics of entanglement between a QD spin qubit and a single photon qubit inside a quantum network node, as well as its robustness against various decoherence processes. First, the entanglement dynamics is considered without decoherence. In the small detuning regime (Δ=78 μeV), there are three different conditions for maximum entanglement, which occur after 71, 93, and 116 picoseconds of interaction time. In the large detuning regime (Δ=1.5 meV), there is only one peak for maximum entanglement occurring at 625 picoseconds. Second, the entanglement dynamics is considered with decoherence by including the effects of spin-nucleus and hole-nucleus hyperfine interactions. In the small detuning regime, a decent amount of entanglement (35% entanglement) can only be obtained within 200 picoseconds of interaction. Afterward, all entanglement is lost. In the large detuning regime, a smaller amount of entanglement is realized, namely, 25%. And, it lasts only within the first 300 picoseconds.

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3

Cardona-Serra, Salvador, Luis Escalera-Moreno, José J. Baldoví, Alejandro Gaita-Ariño, Juan M. Clemente-Juan, and Eugenio Coronado. "SIMPRE1.2: Considering the hyperfine and quadrupolar couplings and the nuclear spin bath decoherence." Journal of Computational Chemistry 37, no. 13 (February 2, 2016): 1238–44. http://dx.doi.org/10.1002/jcc.24313.

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4

Zhou, Xu, Qing-Kun Wan, and Xiao-Hui Wang. "Many-Body Dynamics and Decoherence of the XXZ Central Spin Model in External Magnetic Field." Entropy 22, no. 1 (December 23, 2019): 23. http://dx.doi.org/10.3390/e22010023.

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The many-body dynamics of an electron spin−1/2 qubit coupled to a bath of nuclear spins by hyperfine interactions, as described by the central spin model in two kinds of external field, are studied in this paper. In a completely polarized bath, we use the state recurrence method to obtain the exact solution of the X X Z central spin model in a constant magnetic field and numerically analyze the influence of the disorder strength of the magnetic field on fidelity and entanglement entropy. For a constant magnetic field, the fidelity presents non-attenuating oscillations. The anisotropic parameter λ and the magnetic field strength B significantly affect the dynamic behaviour of the central spin. Unlike the periodic oscillation in the constant magnetic field, the decoherence dynamics of the central spin act like a damping oscillation in a disordered field, where the central spin undergoes a relaxation process and eventually reaches a stable state. The relaxation time of this process is affected by the disorder strength and the anisotropic parameter, where a larger anisotropic parameter or disorder strength can speed up the relaxation process. Compared with the constant magnetic field, the disordered field can regulate the decoherence over a large range, independent of the anisotropic parameter.

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5

Collett, Charles, Kai-Isaak Ellers, Nicholas Russo, Kevin Kittilstved, Grigore Timco, Richard Winpenny, and Jonathan Friedman. "A Clock Transition in the Cr7Mn Molecular Nanomagnet." Magnetochemistry 5, no. 1 (January 14, 2019): 4. http://dx.doi.org/10.3390/magnetochemistry5010004.

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A viable qubit must have a long coherence time T 2 . In molecular nanomagnets, T 2 is often limited at low temperatures by the presence of dipole and hyperfine interactions, which are often mitigated through sample dilution, chemical engineering and isotope substitution in synthesis. Atomic-clock transitions offer another route to reducing decoherence from environmental fields by reducing the effective susceptibility of the working transition to field fluctuations. The Cr7Mn molecular nanomagnet, a heterometallic ring, features a clock transition at zero field. Both continuous-wave and spin-echo electron-spin resonance experiments on Cr7Mn samples, diluted via co-crystallization, show evidence of the effects of the clock transition with a maximum T 2 ∼ 390 ns at 1.8 K. We discuss improvements to the experiment that may increase T 2 further.

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6

Rajagopal, A. K., S. D. Mahanti, and Sudhanshu S. Jha. "Decoherence and fidelity of single-electron spin states in quantum dots: effects of nuclear hyperfine coupling and double occupancy." Journal of Physics: Condensed Matter 18, no. 47 (November 13, 2006): 10677–91. http://dx.doi.org/10.1088/0953-8984/18/47/013.

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7

Zaripov, Ruslan, Evgeniya Vavilova, Iskander Khairuzhdinov, Kev Salikhov, Violeta Voronkova, Mohammad A. Abdulmalic, Francois E. Meva, et al. "Tuning the spin coherence time of Cu(II)−(bis)oxamato and Cu(II)−(bis)oxamidato complexes by advanced ESR pulse protocols." Beilstein Journal of Nanotechnology 8 (April 27, 2017): 943–55. http://dx.doi.org/10.3762/bjnano.8.96.

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We have investigated with the pulsed ESR technique at X- and Q-band frequencies the coherence and relaxation of Cu spins S = 1/2 in single crystals of diamagnetically diluted mononuclear [n-Bu4N]2[Cu(opba)] (1%) in the host lattice of [n-Bu4N]2[Ni(opba)] (99%, opba = o-phenylenebis(oxamato)) and of diamagnetically diluted mononuclear [n-Bu4N]2[Cu(opbon-Pr2)] (1%) in the host lattice of [n-Bu4N]2[Ni(opbon-Pr2)] (99%, opbon-Pr2 = o-phenylenebis(N(propyl)oxamidato)). For that we have measured the electron spin dephasing time T m at different temperatures with the two-pulse primary echo and with the special Carr–Purcell–Meiboom–Gill (CPMG) multiple microwave pulse sequence. Application of the CPMG protocol has led to a substantial increase of the spin coherence lifetime in both complexes as compared to the primary echo results. It shows the efficiency of the suppression of the electron spin decoherence channel in the studied complexes arising due to spectral diffusion induced by a random modulation of the hyperfine interaction with the nuclear spins. We argue that this method can be used as a test for the relevance of the spectral diffusion for the electron spin decoherence. Our results have revealed a prominent role of the opba4– and opbon-Pr2 4– ligands for the dephasing of the Cu spins. The presence of additional 14N nuclei and protons in [Cu(opbon-Pr2)]2– as compared to [Cu(opba)]2– yields significantly shorter T m times. Such a detrimental effect of the opbon-Pr2 4− ligands has to be considered when discussing a potential application of the Cu(II)−(bis)oxamato and Cu(II)−(bis)oxamidato complexes as building blocks of more complex molecular structures in prototype spintronic devices. Furthermore, in our work we propose an improved CPMG pulse protocol that enables elimination of unwanted echoes that inevitably appear in the case of inhomogeneously broadened ESR spectra due to the selective excitation of electron spins.

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8

Hung, Jo-Tzu, Jianjia Fei, Mark Friesen, and Xuedong Hu. "Decoherence of an exchange qubit by hyperfine interaction." Physical Review B 90, no. 4 (July 18, 2014). http://dx.doi.org/10.1103/physrevb.90.045308.

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9

Troiani, Filippo, Dimitrije Stepanenko, and Daniel Loss. "Hyperfine-induced decoherence in triangular spin-cluster qubits." Physical Review B 86, no. 16 (October 17, 2012). http://dx.doi.org/10.1103/physrevb.86.161409.

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10

Yang, Pengfei, Gang Li, Zhihui Wang, Pengfei Zhang, and Tiancai Zhang. "Gate fidelity, dephasing, and “magic” trapping of optically trapped neutral atom." New Journal of Physics, August 8, 2022. http://dx.doi.org/10.1088/1367-2630/ac87ca.

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Abstract The fidelity of the gate operation and the coherence time of neutral atoms trapped in an optical dipole trap are figures of merit for the applications. The motion of the trapped atom is one of the key factors which influence the gate fidelity and coherence time. However, it has been considered as a classical oscillator in analysis of the coherence time. Here we treat the motion as a quantum oscillator, and the population on the vibrational states of the atom are taken into account in analyzing the gate fidelity and decoherence. We show that the fidelity of a coherent rotation gate between two hyperfine states is dramatically limited by the population distribution on the vibrational states. We also find that the description of the decoherence caused by the previously regarded inhomogeneous dephasing due to the thermal motion of the atom is actually homogeneous in a quantum view. The phase between the two hyperfine states is still preserved on different vibrational states, and the observed interference fringe will recover naturally if the differential frequency shift is stable and the vibrational states do not change. The decoherence due to the fluctuations of the trap laser intensity is also discussed. Both the gate fidelity and coherence time can be dramatically enhanced by cooling the atom into vibrational ground states and/or by using a blue-detuned trap. More importantly, we propose a ``magic'' trapping condition by preparing the atom into specific vibrational states.

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11

Zhang, Wenxian, V. V. Dobrovitski, K. A. Al-Hassanieh, E. Dagotto, and B. N. Harmon. "Hyperfine interaction induced decoherence of electron spins in quantum dots." Physical Review B 74, no. 20 (November 14, 2006). http://dx.doi.org/10.1103/physrevb.74.205313.

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12

Fuchs, Moritz, Valentin Rychkov, and Björn Trauzettel. "Spin decoherence in graphene quantum dots due to hyperfine interaction." Physical Review B 86, no. 8 (August 1, 2012). http://dx.doi.org/10.1103/physrevb.86.085301.

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13

Witzel, W. M., Xuedong Hu, and S. Das Sarma. "Decoherence induced by anisotropic hyperfine interaction in Si spin qubits." Physical Review B 76, no. 3 (July 31, 2007). http://dx.doi.org/10.1103/physrevb.76.035212.

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14

Rajh, Tijana, Lei Sun, Shobhit Gupta, Jun Yang, Haitao Zhang, and Tian Zhong. "Hyperfine Interactions and Coherent Spin Dynamics of Isotopically Purified 167Er3+ in Polycrystalline Y2O3." Materials for Quantum Technology, October 28, 2022. http://dx.doi.org/10.1088/2633-4356/ac9e86.

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Abstract 167Er3+ doped solids are a promising platform for quantum technology due to erbium’s telecom C-band optical transition and its long hyperfine coherence times. We experimentally study the spin Hamiltonian and dynamics of 167Er3+ spins in Y2O3 using electron paramagnetic resonance (EPR) spectroscopy. The anisotropic electron Zeeman, hyperfine and nuclear quadrupole matrices are fitted using data obtained by X-band (9.5 GHz) EPR spectroscopy. We perform pulsed EPR spectroscopy to measure spin relaxation time T1 and coherence time T2 for the 3 principal axes of an anisotropic g tensor. Long electronic spin coherence time up to 24.4 μs is measured for lowest g transition at 4 K, exceeding previously reported values at much lower temperatures. Measurements of decoherence mechanism indicates T2 limited by spectral diffusion and instantaneous diffusion. Long spin coherence times, along with a strong anisotropic hyperfine interaction makes 167Er3+:Y2O3 a rich system and an excellent candidate for spin-based quantum technologies.

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15

Haykal, A., R. Tanos, N. Minotto, A. Durand, F. Fabre, J. Li, J. H. Edgar, et al. "Decoherence of V$${}_{{{{{{{{\rm{B}}}}}}}}}^{-}$$ spin defects in monoisotopic hexagonal boron nitride." Nature Communications 13, no. 1 (July 27, 2022). http://dx.doi.org/10.1038/s41467-022-31743-0.

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AbstractSpin defects in hexagonal boron nitride (hBN) are promising quantum systems for the design of flexible two-dimensional quantum sensing platforms. Here we rely on hBN crystals isotopically enriched with either 10B or 11B to investigate the isotope-dependent properties of a spin defect featuring a broadband photoluminescence signal in the near infrared. By analyzing the hyperfine structure of the spin defect while changing the boron isotope, we first confirm that it corresponds to the negatively charged boron-vacancy center ($${{{{{{{{\rm{V}}}}}}}}}_{{{{{{{{\rm{B}}}}}}}}}^{-}$$ V B − ). We then show that its spin coherence properties are slightly improved in 10B-enriched samples. This is supported by numerical simulations employing cluster correlation expansion methods, which reveal the importance of the hyperfine Fermi contact term for calculating the coherence time of point defects in hBN. Using cross-relaxation spectroscopy, we finally identify dark electron spin impurities as an additional source of decoherence. This work provides new insights into the properties of $${{{{{{{{\rm{V}}}}}}}}}_{{{{{{{{\rm{B}}}}}}}}}^{-}$$ V B − spin defects, which are valuable for the future development of hBN-based quantum sensing foils.

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16

Hetényi, Bence, Péter Boross, and András Pályi. "Hyperfine-assisted decoherence of a phosphorus nuclear-spin qubit in silicon." Physical Review B 100, no. 11 (September 27, 2019). http://dx.doi.org/10.1103/physrevb.100.115435.

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17

Un, Sun, Sebastian de Graaf, Patrice Bertet, Sergey Kubatkin, and Andrey Danilov. "On the nature of decoherence in quantum circuits: Revealing the structural motif of the surface radicals in α-Al ₂ O ₃." Science Advances 8, no. 14 (April 8, 2022). http://dx.doi.org/10.1126/sciadv.abm6169.

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Quantum information technology puts stringent demands on the quality of materials and interfaces in the pursuit of increased device coherence. Yet, little is known about the chemical structure and origins of paramagnetic impurities that produce flux/charge noise that causes decoherence of fragile quantum states and impedes the progress toward large-scale quantum computing. Here, we perform high magnetic field electron paramagnetic resonance (HFEPR) and hyperfine multispin spectroscopy on α-Al 2 O 3 , a common substrate for quantum devices. In its amorphous form, α-Al 2 O 3 is also unavoidably present in aluminum-based superconducting circuits and qubits. The detected paramagnetic centers are immanent to the surface and have a well-defined but highly complex structure that extends over multiple hydrogen, aluminum, and oxygen atoms. Modeling reveals that the radicals likely originate from well-known reactive oxygen chemistry common to many metal oxides. We discuss how EPR spectroscopy might benefit the search for surface passivation and decoherence mitigation strategies.

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18

Park, Huijin, Junghyun Lee, Sangwook Han, Sangwon Oh, and Hosung Seo. "Decoherence of nitrogen-vacancy spin ensembles in a nitrogen electron-nuclear spin bath in diamond." npj Quantum Information 8, no. 1 (August 12, 2022). http://dx.doi.org/10.1038/s41534-022-00605-4.

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AbstractNitrogen-vacancy (NV) centers in diamond have been developed into essential hardware units for a wide range of solid-state-based quantum technology applications. While such applications require the long spin lifetimes of the NV centers, they are often limited due to decoherence. In this study, we theoretically investigate the decoherence of NV-spin ensembles induced by nitrogen impurities (P1 centers), which are one of the most dominant and inevitable magnetic field noise sources in diamond. We combined cluster correlation expansion and density functional theory to compute the Hahn-echo spin-coherence time of the NV centers for a broad range of P1 concentrations. Results indicate a clear linear dependence of T2 on P1 concentrations on a log scale with a slope of −1.06, which is in excellent agreement with previous experimental results. The interplay between the Jahn–Teller effect and the hyperfine interaction in the P1 center plays a critical role in determining the bath dynamics and the resulting NV decoherence. Our results provide a theoretical upper bound for the NV-spin T2 over a wide range of P1 densities, serving as a key reference for materials optimization and spin bath characterization to develop highly coherent NV-based devices for quantum information technology.

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19

Amaro, Pedro, A. Adamczak, M. Abdou Ahmed, L. Affolter, F. D. Amaro, Patricia Carvalho, T. L. Chen, et al. "Laser excitation of the 1s-hyperfine transition in muonic hydrogen." SciPost Physics 13, no. 2 (August 15, 2022). http://dx.doi.org/10.21468/scipostphys.13.2.020.

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The CREMA collaboration is pursuing a measurement of the ground-state hyperfine splitting (HFS) in muonic hydrogen (\muμp) with 1 ppm accuracy by means of pulsed laser spectroscopy to determine the two-photon-exchange contribution with 2\times10^{-4}2×10−4 relative accuracy. In the proposed experiment, the \muμp atom undergoes a laser excitation from the singlet hyperfine state to the triplet hyperfine state, {then} is quenched back to the singlet state by an inelastic collision with a H_22 molecule. The resulting increase of kinetic energy after the collisional deexcitation is used as a signature of a successful laser transition between hyperfine states. In this paper, we calculate the combined probability that a \muμp atom initially in the singlet hyperfine state undergoes a laser excitation to the triplet state followed by a collisional-induced deexcitation back to the singlet state. This combined probability has been computed using the optical Bloch equations including the inelastic and elastic collisions. Omitting the decoherence effects caused by {the laser bandwidth and }collisions would overestimate the transition probability by more than a factor of {two in the experimental conditions. Moreover,} we also account for Doppler effects and provide the matrix element, the saturation fluence, the elastic and inelastic collision rates for the singlet and triplet states, and the resonance linewidth. This calculation thus quantifies one of the key unknowns of the HFS experiment, leading to a precise definition of the requirements for the laser system and to an optimization of the hydrogen gas target where \muμp is formed and the laser spectroscopy will occur.

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20

Troiani, F., V. Bellini, and M. Affronte. "Decoherence induced by hyperfine interactions with nuclear spins in antiferromagnetic molecular rings." Physical Review B 77, no. 5 (February 21, 2008). http://dx.doi.org/10.1103/physrevb.77.054428.

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21

Faribault, Alexandre, and Dirk Schuricht. "Integrability-Based Analysis of the Hyperfine-Interaction-Induced Decoherence in Quantum Dots." Physical Review Letters 110, no. 4 (January 25, 2013). http://dx.doi.org/10.1103/physrevlett.110.040405.

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22

Maier, Franziska, and Daniel Loss. "Effect of strain on hyperfine-induced hole-spin decoherence in quantum dots." Physical Review B 85, no. 19 (May 24, 2012). http://dx.doi.org/10.1103/physrevb.85.195323.

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23

Arfaoui, Mehdi, and Sihem Jaziri. "Decoherence of a spin-valley qubit in a MoS₂ quantum dot." Journal of Physics Communications, November 14, 2022. http://dx.doi.org/10.1088/2399-6528/aca270.

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Abstract Transition metal dichalcogenide (TMD)-based quantum dots (QDs) have proven to be a successful and promising device for physically implementing electron spin-valley based qubits. Although the electron spin in a TMDs monolayer semiconductor QD can be isolated and controlled with high precision, decoherence occurs due to unavoidable coupling with the surrounding environment, such as nuclear spin environments. In this paper, using an exact master equation (ME) of spin qubit dynamics coupled to a nuclear spin bath in terms of hyperfine interaction (HI), we have investigated the controllability of dynamics processes with varying degrees of non-Markovianity. In large magnetic fields, we show that pure spin or valley qubits can be created. We calculate the loss of fidelity due to the Overhauser field of HI in a wide range of nuclear spin N. In this context, we prove that this field restricts the decoherence process of the central electron spin, which can regain its coherence. Finally, we discuss how the coherence of the spin qubit remains robust for large N.

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24

Jeschke, Gunnar. "Rotational Coupling in Methyl-Tunneling Electron Spin Echo Envelope Modulation." Applied Magnetic Resonance, July 14, 2021. http://dx.doi.org/10.1007/s00723-021-01375-6.

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AbstractCoherence between tunnel-split states of a methyl quantum rotor can be generated and observed in stimulated and spin-locked echo experiments, if hyperfine coupling of a nearby electron spin to the methyl protons breaks C$$_3$$ 3 symmetry and is of the same order of magnitude as the tunnel splitting. Here, we consider the case of two methyl groups bound to the same sp$$^{3}$$ 3 -hybridized atom, which is important in the context of common nitroxide spin labels. For a simple form of the rotor-rotor coupling Hamiltonian, we provide an approach that allows for density operator computations of this system with 1152 quantum states with moderate computational effort. We find that, in the regime where the ratio between rotor-rotor coupling and rotational barrier is much smaller than unity, three-pulse ESEEM and hyperfine-decoupled ESEEM depend only on the tunnel splitting, but not on this ratio. This finding may simplify the treatment of tunnel-induced electron decoherence in systems where the methyl groups are bound to sp$$^{3}$$ 3 -hybridized atoms.

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25

Deng, Changxue, and Xuedong Hu. "Analytical solution of electron spin decoherence through hyperfine interaction in a quantum dot." Physical Review B 73, no. 24 (June 7, 2006). http://dx.doi.org/10.1103/physrevb.73.241303.

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26

Fujita, T., P. Stano, G. Allison, K. Morimoto, Y. Sato, M. Larsson, J. H. Park, et al. "Signatures of Hyperfine, Spin-Orbit, and Decoherence Effects in a Pauli Spin Blockade." Physical Review Letters 117, no. 20 (November 11, 2016). http://dx.doi.org/10.1103/physrevlett.117.206802.

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27

Fischer, Jan, Björn Trauzettel, and Daniel Loss. "Hyperfine interaction and electron-spin decoherence in graphene and carbon nanotube quantum dots." Physical Review B 80, no. 15 (October 1, 2009). http://dx.doi.org/10.1103/physrevb.80.155401.

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28

Yu, Siqing, Yechao Zhu, and Ye Yeo. "Hyperfine-interaction-induced decoherence and deterministic teleportation of electrons in a quantum-dot nanostructure." Physical Review A 77, no. 6 (June 27, 2008). http://dx.doi.org/10.1103/physreva.77.062338.

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29

Choi, Yujun, and Robert Joynt. "Anisotropy with respect to the applied magnetic field of spin qubit decoherence times." npj Quantum Information 8, no. 1 (June 21, 2022). http://dx.doi.org/10.1038/s41534-022-00576-6.

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AbstractElectron spin qubits are a promising platform for quantum computation. Environmental noise impedes coherent operations by limiting the qubit relaxation (T1) and dephasing (Tϕ) times. There are multiple sources of such noise, which makes it important to devise experimental techniques that can detect the spatial locations of these sources and determine the type of source. In this paper, we propose that anisotropy in T1 and Tϕ with respect to the direction of the applied magnetic field can reveal much about these aspects of the noise. We investigate the anisotropy patterns of charge noise, evanescent-wave Johnson noise, and hyperfine noise in hypothetical devices. It is necessary to have a rather well-characterized sample to get the maximum benefit from this technique. The general anisotropy patterns are elucidated. We calculate the expected anisotropy for a particular model of a Si/SiGe quantum dot device.

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30

Wang, Xin, Edwin Barnes, and S. Das Sarma. "Improving the gate fidelity of capacitively coupled spin qubits." npj Quantum Information 1, no. 1 (October 27, 2015). http://dx.doi.org/10.1038/npjqi.2015.3.

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AbstractCapacitively coupled semiconductor spin qubits hold promise as the building blocks of a scalable quantum computing architecture with long-range coupling between distant qubits. However, the two-qubit gate fidelities achieved in experiments to date have been severely limited by decoherence originating from charge noise and hyperfine interactions with nuclear spins, and are currently unacceptably low for any conceivable multi-qubit gate operations. Here, we present control protocols that implement two-qubit entangling gates while substantially suppressing errors due to both types of noise. These protocols are obtained by making simple modifications to control sequences already used in the laboratory and should thus be easy enough for immediate experimental realisation. Together with existing control protocols for robust single-qubit gates, our results constitute an important step toward scalable quantum computation using spin qubits in semiconductor platforms.

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31

Zhang, Wenxian, N. P. Konstantinidis, V. V. Dobrovitski, B. N. Harmon, Lea F. Santos, and Lorenza Viola. "Long-time electron spin storage via dynamical suppression of hyperfine-induced decoherence in a quantum dot." Physical Review B 77, no. 12 (March 27, 2008). http://dx.doi.org/10.1103/physrevb.77.125336.

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32

Deng, Changxue, and Xuedong Hu. "Erratum: Analytical solution of electron spin decoherence through hyperfine interaction in a quantum dot [Phys. Rev. B73, 241303(R) (2006)]." Physical Review B 74, no. 12 (September 1, 2006). http://dx.doi.org/10.1103/physrevb.74.129902.

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33

Zhang, Wenxian, N. P. Konstantinidis, V. V. Dobrovitski, B. N. Harmon, Lea F. Santos, and Lorenza Viola. "Publisher's Note: Long-time electron spin storage via dynamical suppression of hyperfine-induced decoherence in a quantum dot [Phys. Rev. B77, 125336 (2008)]." Physical Review B 77, no. 15 (April 7, 2008). http://dx.doi.org/10.1103/physrevb.77.159902.

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34

Deng, Changxue, and Xuedong Hu. "Publisher's Note: Erratum: Analytical solution of electron spin decoherence through hyperfine interaction in a quantum dot [Phys. Rev. B73, 241303(R) (2006)] [Phys. Rev. B74, 129902(E) (2006)]." Physical Review B 74, no. 12 (September 19, 2006). http://dx.doi.org/10.1103/physrevb.74.129903.

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35

Band, Yehuda B., and Yonathan Japha. "Tuning the adiabaticity of spin dynamics in diamond nitrogen vacancy centers." Journal of Physics: Condensed Matter, March 24, 2022. http://dx.doi.org/10.1088/1361-648x/ac60d1.

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Abstract We study the spin dynamics of diamond nitrogen vacancy (NV) centers in an oscillating magnetic field along the symmetry axis of the NV in the presence of transverse magnetic fields. It is well-known that the coupling between the otherwise degenerate Zeeman levels $|M_S=\pm1\rangle$ due to strain and electric fields is responsible for a Landau-Zener process near the pseudo-crossing of the adiabatic energy levels when the axial component of the oscillating magnetic field changes sign. We derive an effective two-level Hamiltonian for the NV system that includes coupling between the two levels via virtual transitions into the third far-detuned level $|M_S=0\rangle$ induced by transverse magnetic fields. This coupling adds to the coupling due to strain and electric fields, with a phase that depends on the direction of the transverse field in the plane perpendicular to the NV axis. Hence, the {\em total coupling} of the Zeeman levels can be tuned to control the adiabaticity of spin dynamics by fully or partially compensating the effect of the strain and electric fields, or by enhancing it. Moreover, by varying the strength and direction of the transverse magnetic fields, one can determine the strength and direction of the local strain and electric fields at the position of the NV center, and even the {\em external} stress and electric field. The nuclear spin hyperfine interaction is shown to introduce a nuclear spin dependent offset of the axial magnetic field for which the pseudo-crossing occurs, while the adiabaticity remains unaffected by the nuclear spin. If the NV center is coupled to the environment, modeled by a bath with a Gaussian white noise spectrum, as appropriate for NVs near the diamond surface, then the spin dynamics is accompanied by relaxation of the Zeeman level populations and decoherence with a non-monotonic decrease of the purity of the system. The results presented here have important impact for metrology with NV centers, quantum control of spin systems in solids and coupled dynamics of spin and rotations in levitated nano-objects in the presence of magnetic fields.

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