Before switching field to biophysics and quit my previous PhD, I design and fabricate different graphene nano-electronics. I am quite proud of these Graphene & Superconductor hybrid devices we made 2013-2014. Graphene monolayers or bilayers deposited on doped silicon chips by mechanical exfoliation. Two graphene double quantum dots (DQDs) are fabricated within the same alignment array and a reflection line resonator (RLR) is fabricated to connect the gates of the DQDs.
With this architecture, we successfully characterized the decoherence time (T2) of the charge states in graphene DQDs and see the distant coupling between two states mediated by the photons in the resonator. The results are published in Nano Letters 15, 10, 6620–6625 (2015): Coupling Two Distant Double Quantum Dots with a Microwave Resonator and in Physical Review Letters 115: 126804 (2015): Charge Number Dependence of the Dephasing Rates of a Graphene Double Quantum Dot in a Circuit QED Architecture and in Chinese Physics Letters 33(04):047301 : Multiplexing Read-Out of Charge Qubits by a Superconducting Resonator I am in charge of the sample design, fabrication, part of the measurement and analysis. I am very proud to conceive and initiate the project together with my friends and colleagues. Starting from this project, I realized how much I enjoy close collaborations and how much I enjoy making "whimsical" ideas come true.
Locked in the cleanroom, sang in the huge noise of those mechanical pumps and molecular pumps. Nothing worked and tens of hours were used in making samples that later proved to be trash. This is how I remembered the year 2011 to 2013. I made it in the end and the production of graphene nano-electronics is no longer a problem. I implement a modified measurement scheme of the electron temperature and realized that it can also tell the tunnelling rate between the quantum dots.
The work is published in Scientific Reports 3: 3175 (2013): Tuning inter-dot tunnel coupling of an etched graphene double quantum dot by adjacent metal gates This is my first-ever first-authored scientific publication and is also the first time me going through the whole process from submission to final textual check. A modified measurement scheme of the electron temperature, which also reads the inter-dot tunnelling rate, is published in Applied Physics Letters 105(7): 073510 (2014): Measuring the complex admittance of a nearly isolated graphene quantum dot.