Theory on electron-phonon spin dehphasing in GaAs multi-electron double quantum dots

• URL: http://arxiv.org/abs/2203.16138v1
• Date: Wed, 30 Mar 2022 08:25:18 GMT
• Title: Theory on electron-phonon spin dehphasing in GaAs multi-electron double quantum dots
• Authors: Guanjie He, Guo Xuan Chan, Xin Wang
• Abstract summary: We study the electron-phonon dephasing occurring in a GaAs multi-electron double-quantum-dot system. We have found that while the electron-phonon dephasing rate increases with the number of electrons confined in the unbiased case, this does not hold in the biased case.
• Score: 6.211541620389987
• License: http://arxiv.org/licenses/nonexclusive-distrib/1.0/
• Abstract: Recent studies reveal that a double-quantum-dot system hosting more than two electrons may be superior in certain aspects as compared to the traditional case in which only two electrons are confined (a singlet-triplet qubit). We study the electron-phonon dephasing occurring in a GaAs multi-electron double-quantum-dot system, in a biased case in which the singlet state is hybridized, as well as in an unbiased case in which the hybridization is absent. We have found that while the electron-phonon dephasing rate increases with the number of electrons confined in the unbiased case, this does not hold in the biased case. We define a merit figure as a ratio between the exchange energy and the dephasing rate, and have shown that in experimentally relevant range of the exchange energy, the merit figure actually increases with the number of electrons in the biased case. Our results show that the multi-electron quantum-dot system has another advantage in mitigating the effect of electron-phonon dephasing, which is previously under-appreciated in the literature.

Related papers

• Testing spooky action between free-traveling electron-positron pairs [4.004507057677153]
  We investigate the entanglement and the Bell inequality violation of free-traveling electron-positron pairs generated in a fixed-target experiment. Based on this source and the prior knowledge of the entangled state, we demonstrate the feasibility of measuring the polarization correlations of the entangled $e+e-$ pairs.
  arXiv  Detail & Related papers  (2025-02-11T14:46:49Z)
• Electrons herald non-classical light [0.44270590458998854]
  We demonstrate the coherent parametric generation of non-classical states of light by free electrons. We show that the quantized electron energy loss heralds the number of photons generated in a dielectric waveguide. The approach facilitates the tailored preparation of higher-number Fock and other optical quantum states.
  arXiv  Detail & Related papers  (2024-09-17T15:55:54Z)
• Tomography of entangling two-qubit logic operations in exchange-coupled donor electron spin qubits [26.72272277499726]
  Quantum processors require high-fidelity universal quantum logic operations. No entanglement between donor-bound electron spins has been demonstrated to date. These results form the necessary basis for scaling up donor-based quantum computers.
  arXiv  Detail & Related papers  (2023-09-27T07:58:37Z)
• A Hybrid Quantum-Classical Method for Electron-Phonon Systems [40.80274768055247]
  We develop a hybrid quantum-classical algorithm suitable for this type of correlated systems. This hybrid method tackles with arbitrarily strong electron-phonon coupling without increasing the number of required qubits and quantum gates. We benchmark the new method by applying it to the paradigmatic Hubbard-Holstein model at half filling, and show that it correctly captures the competition between charge density wave and antiferromagnetic phases.
  arXiv  Detail & Related papers  (2023-02-20T08:08:51Z)
• Quantum interaction of sub-relativistic aloof electrons with mesoscopic samples [91.3755431537592]
  Relativistic electrons experience very slight wave packet distortion and negligible momentum recoil when interacting with nanometer-sized samples. Modelling fast electrons as classical point-charges provides extremely accurate theoretical predictions of energy-loss spectra.
  arXiv  Detail & Related papers  (2022-11-14T15:22:37Z)
• Single quantum emitters with spin ground states based on Cl bound excitons in ZnSe [55.41644538483948]
  We show a new type of single photon emitter with potential electron spin qubit based on Cl impurities inSe. Results suggest single Cl impurities are suitable as single photon source with potential photonic interface.
  arXiv  Detail & Related papers  (2022-03-11T04:29:21Z)
• Microscopic theory on magnetic-field-tuned sweet spot of exchange interactions in multielectron quantum-dot systems [7.33811357166334]
  We study a singlet-triplet qubit defined by four-electron states in the double-quantum-dot system. We show that the exchange energy as a function of detuning can be non-monotonic, suggesting existence of sweet spots. Our results suggest that a singlet-triplet qubit with more than two electrons can have advantages in the realization of quantum computing.
  arXiv  Detail & Related papers  (2022-02-04T18:45:37Z)
• Magnetic response of interacting electrons in a spatially non-uniform disordered multi-channel system: Exact and mean-field results [0.0]
  In this work we explore magnetic response of interacting electrons in a spatially non-uniform disordered system. The interaction among the electrons are taken in the well known Hubbard form which leads to several anomalous features in energy spectra and flux driven circular current. Our detailed analysis may be utilized to study magnetic response of interacting electrons in other similar kind of non-uniform disordered systems.
  arXiv  Detail & Related papers  (2021-12-01T12:14:59Z)
• Mesoscopic quantum superposition states of weakly-coupled matter-wave solitons [58.720142291102135]
  We establish quantum features of an atomic soliton Josephson junction (SJJ) device. We show that the SJJ-model in quantum domain exhibits unusual features due to its effective nonlinear strength proportional to the square of total particle number. We have shown that the obtained quantum state is more resistant to few particle losses from the condensates if tiny components of entangled Fock states are present.
  arXiv  Detail & Related papers  (2020-11-26T09:26:19Z)
• The impact of electron-electron correlation in ultrafast attosecond single ionization dynamics [38.98439939494304]
  We investigate the attosecond ultrafast ionization dynamics of correlated two- or many-electron systems. We find that different pathways result in a difference in the electronic population of the parent molecular ion.
  arXiv  Detail & Related papers  (2020-02-25T16:00:20Z)
• Analytical view on tunnable electrostatic quantum swap gate in tight-binding model [0.0]
  Generalized electrostatic quantum swap gate implemented in the chain of 2 double coupled quantum dots using single electron in semiconductor is presented. The anticorrelation principle coming from Coulomb electrostatic repulsion is exploited in single electron devices. The formation of quantum entanglement is specified and supported by analytical results.
  arXiv  Detail & Related papers  (2020-01-07T02:20:27Z)

This list is automatically generated from the titles and abstracts of the papers in this site.

This site does not guarantee the quality of this site (including all information) and is not responsible for any consequences.