##
Single-electron double quantum dot dipole-coupled to a single
photonic mode

### Julien Basset

**Tuesday, 22 October 2013, 11:00**

Seminar room F

**Abstract**:

We have realized a hybrid solid-state quantum device in which a
single-electron semiconductor double quantum dot is dipole coupled to a
superconducting microwave frequency transmission line resonator. The
dipolar interaction between the two entities manifests itself via
dispersive and dissipative effects observed as frequency shifts and
linewidth broadenings of the photonic mode respectively. A
Jaynes-Cummings Hamiltonian master equation calculation is used to model
the combined system response and allows for determining both the
coherence properties of the double quantum dot and its interdot tunnel
coupling with high accuracy. The value and uncertainty of the tunnel
coupling extracted from the microwave read-out technique are compared to
a standard quantum point contact charge detection analysis. The two
techniques are found to be consistent with a superior precision for the
microwave experiment when tunneling rates approach the resonator
eigenfrequency. Decoherence properties of the double dot are further
investigated as a function of the number of electrons inside the dots.
They are found to be similar in the single-electron and many-electron
regimes suggesting that the density of the confinement energy spectrum
plays a minor role in the decoherence rate of the system under
investigation.