Charge Number Dependence of the Dephasing Rates of a Graphene Double Quantum Dot in a Circuit QED Architecture.

  title={Charge Number Dependence of the Dephasing Rates of a Graphene Double Quantum Dot in a Circuit QED Architecture.},
  author={Guang-Wei Deng and Da Wei and J. R. Johansson and Miao Zhang and Shu-Xiao Li and Hai-Ou Li and Gang Cao and Ming Xiao and Tao Tu and Guangcan Guo and Hongwen Jiang and Franco Nori and Guo-Ping Guo},
  journal={Physical review letters},
  volume={115 12},
We use an on-chip superconducting resonator as a sensitive meter to probe the properties of graphene double quantum dots at microwave frequencies. Specifically, we investigate the charge dephasing rates in a circuit quantum electrodynamics architecture. The dephasing rates strongly depend on the number of charges in the dots, and the variation has a period of four charges, over an extended range of charge numbers. Although the exact mechanism of this fourfold periodicity in dephasing rates is… 

Figures from this paper

Charge noise acting on graphene double quantum dots in circuit quantum electrodynamics architecture
We investigate the dephasing mechanisms induced by the charge noise and microwave heating effect acting on a graphene double quantum dot (DQD) capacitively coupled to a microwave resonator. The
Circuit quantum electrodynamics architecture for gate-defined quantum dots in silicon
We demonstrate a hybrid device architecture where the charge states in a double quantum dot (DQD) formed in a Si/SiGe heterostructure are read out using an on-chip superconducting microwave cavity. A
Microwaves as a probe of quantum dot circuits: from Kondo dynamics to mesoscopic quantum electrodynamics
This thesis uses microwaves as probe of carbon nanotube quantum dot circuits. In a first experiment, a microwave excitation is directly applied to a circuit electrode for a quantum dot in the Kondo
Shaping the spectrum of carbon nanotube quantum dots with superconductivity and ferromagnetism for mesoscopic quantum electrodynamics
In this thesis, we study carbon nanotubes based quantum dot circuits embedded in a microwave cavity. This general architecture allows one to simultaneously probe the circuit via quantum transport
Theory of valley-resolved spectroscopy of a Si triple quantum dot coupled to a microwave resonator.
Theoretical methods include a capacitor model to fit experimental charging energies, an extended Hubbard model to describe the tunneling dynamics, a rate equation model to find the occupation probabilities, and an input-output model to determine the response signal of the resonator.
InSb nanowire double quantum dots coupled to a superconducting microwave cavity
By employing a micrometer precision mechanical transfer technique, we embed individual InSb nanowires into a superconducting coplanar waveguide resonator. We investigate the characteristics of a
Suspending Effect on Low-Frequency Charge Noise in Graphene Quantum Dot
The 1/f noise for a microscopic graphene QD is substantially larger than that for a macroscopic graphene field-effect transistor (FET), increasing linearly with temperature, thus affecting the coherency of graphene nano-devices.
Coherent transport in Y-junction graphene waveguide.
A series of theoretical transport studies on Y-branch electron waveguides which are embedded in mid-size armchair graphene nanoribbons are performed, indicating the existence of valley degree of freedom and the lift of valley degeneracy.
Coupling a single nitrogen-vacancy center with a superconducting qubit via the electro-optic effect
We propose an efficient scheme for transferring quantum states and generating entangled states between two qubits of different nature. The hybrid system consists a single nitrogen vacancy (NV) center


A prototype probability package named APPL (A Probability Programming Language) is presented that can be used to manipulate random variables and examples illustrate its use.
  • Rev. Lett. 108, 046807
  • 2012
  • Rev. Lett. 110, 066802
  • 2013
  • Rep. 3, 3175
  • 2013
  • Mod. Phys. 85, 961
  • 2013
  • Commun. 4, 1753
  • 2013
  • Phys. 4, 536
  • 2008
  • Rev. B 89, 195127
  • 2014
  • Rev. Lett. 92, 226801
  • 2004