Quantum Fingerprints in Higher Order Correlators of a Spin Qubit

Abstract

The spin of an electron in a semiconductor quantum dot represents a natural nanoscale solid state qubit. Coupling to nuclear spins leads to decoherence that limits the number of allowed quantum logic operations for this qubit. Traditional approach to characterize decoherence is to explore spin Relaxation and the spin echo, which are equivalent to the studies of the spins 2nd order time-correlator at various external conditions. Here we develop an alternative technique by showing that considerable information about dynamics can be obtained from direct measurements of higher than the 2nd order correlators, which to date have been hindered in semiconductor quantum dots. We show that such correlators are sensitive to pure quantum effects that cannot be explained within the classical framework, and which allow direct determination of ensemble and quantum dephasing times with only repeated projective measurements without the need for coherent spin control. Our method enables studies of pure quantum effects, including tests of the Leggett-Garg type inequalities that rule out local hidden variable interpretation of the spin qubit dynamics.

References in corpus (12)

• Quantum Computing
• Coherent Population Trapping of an Electron Spin in a Single Negatively Charged Quantum Dot
• Hole - Nuclear Spin Interaction in Quantum Dots
• Opening up the Quantum Three-Box Problem with Undetectable Measurements
• Theory of fast optical spin rotation in a quantum dot based on geometric phases and trapped states
• Necessary and sufficient conditions for macroscopic realism from quantum mechanics
• Demagnetization of Quantum Dot Nuclear Spins: Breakdown of the Nuclear Spin Temperature Approach
• Hyperfine interaction induced decoherence of electron spins in quantum dots
• Dynamical control of electron spin coherence in a quantum dot
• Influcence of the nuclear electric quadrupolar interaction on the coherence time of hole- and electron-spins confined in semiconductor quantum dots
• Selective Optical Charge Generation, Storage and Readout in a Single Self Assembled Quantum Dot
• Controlled tunneling induced dephasing of Rabi rotations for ultra-high fidelity hole spin initialization

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• Quantum nonlinear spectroscopy of single nuclear spins
• Magnetic field dependence of the electron spin revival amplitude in periodically pulsed quantum dots
• Leggett-Garg tests of macrorealism: checks for non-invasiveness and generalizations to higher-order correlators
• Spin and reoccupation noise in a single quantum dot beyond the fluctuation-dissipation theorem
• Fine's Theorem for Leggett-Garg tests with an arbitrary number of measurement times
• Characterizing low-frequency qubit noise
• Decay and revival of electron spin polarization in an ensemble of (In,Ga)As quantum dots
• Relationship between subjecting the qubit to dynamical decoupling and to a sequence of projective measurements
• Spectroscopy of classical environmental noise with a qubit subjected to projective measurements
• Long-time coherence in fourth-order spin correlation functions
• Stimulated resonant spin amplification reveals millisecond electron spin coherence time of rare-earth ions in solids
• Qubit-environment entanglement outside of pure decoherence: hyperfine interaction
• Optical Resonance Shift Spin Noise Spectroscopy
• Quantum mechanical treatment of large spin baths
• Characterization of a quasi-static environment with a qubit
• Cross-correlation spectra in interacting quantum dot systems
• Fourth-order spin correlation function in the extended central spin model
• Signatures of long-range spin-spin interactions in an (In,Ga)As quantum dot ensemble
• Statistics of projective measurement on a quantum probe as a witness of noncommutativity of algebra of a probed system
• Phase Diagram of the Dynamics of a Precessing Qubit under Quantum Measurement