Coherent Charge Oscillations in Graphene Quantum Dots
Case Studies
The coherent dynamics of a quantum mechanical two-level system can give rise to quantum interference phenomena and allows for quantum interference spectroscopy. Interference spectroscopy can be exploited to study charge noise and charge decoherence in semiconductor quantum dots (QDs). Bilayer graphene serves as a promising host material for highly tunable QDs with a potential application as spin and valley qubits. Only recently, coherent charge oscillations have been reported in a bilayer graphene double QD. In this system, 𝑇2∗ charge decoherence times have been measured independently using Landau-Zener-Stückelberg-Majorana (LZSM) interference and photon assisted tunneling, consistently yielding 𝑇2∗ -times in a range of 400 to 500 ps1. In this case study, we provide an introduction into the measurement of coherent charge oscillations using a Keysight arbitrary waveform generator (AWG) and an analog microwave source. All experiments are controlled using the lab control and automation software, Labber.