Backaction of a charge detector on a double quantum dot

Abstract

We develop a master equation approach to study the backaction of quantum point contact (QPC) on a double quantum dot (DQD) at zero bias voltage. We reveal why electrons can pass through the zero-bias DQD only when the bias voltage across the QPC exceeds a threshold value determined by the eigenstate energy difference of the DQD. This derived excitation condition agrees well with experiments on QPC-induced inelastic electron tunneling through a DQD [S. Gustavsson et al., Phys. Rev. Lett. 99, 206804(2007)]. Moreover, we propose a new scheme to generate a pure spin current by the QPC in the absence of a charge current.

6 pages, 4 figures

References in corpus (10)

• Single-shot read-out of an individual electron spin in a quantum dot
• Driven coherent oscillations of a single electron spin in a quantum dot
• Frequency-selective single photon detection using a double quantum dot
• Using a quantum dot as a high-frequency shot noise detector
• A double-dot quantum ratchet driven by an independently biased quantum point contact
• Experimental Test of the High-Frequency Quantum Shot Noise Theory in a Quantum Point Contact
• Persistent spin current in a spin-orbit coupling/normal hybrid ring
• Statistical electron excitation in a double quantum dot induced by two independent quantum point contacts
• Using spin bias to manipulate and measure quantum spin in quantum dots
• Electron spin manipulation and resonator readout in a double quantum dot nano-electromechanical system

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• Confidence and Backaction in the Quantum Filter Equation
• Probing the quantum behaviors of a nanomechanical resonator coupled to a double quantum dot
• Coherent Quantum Ratchets Driven by Tunnel Oscillations
• Heat pump driven by the shot noise of a tunnel contact
• Coherence of an Electronic Two-Level System under Continuous Charge Sensing by a Quantum Dot Detector
• Modelling and Control of Quantum Measurement Induced Backaction in Double Quantum Dots
• Conditional counting statistics of electrons tunneling through quantum dot systems measured by a quantum point contact
• Triplet-assisted leakage during singlet-triplet qubit readout with a quantum point contact