Related papers: Charge Offset Stability in Si Single Electron Devi…
We have measured the low-frequency time instability known as charge offset drift of Si/SiO$_2$ single electron devices (SEDs) with and without an overall poly-Si top gate. We find that SEDs with a poly-Si top gate have significantly less…
An Al-AlO_x-Al single-electron transistor (SET) acting as the gate of a narrow (~ 100 nm) metal-oxide-semiconductor field-effect transistor (MOSFET) can induce a vertically aligned Si SET at the Si/SiO_2 interface near the MOSFET channel…
Charge noise can be detrimental to the operation of quantum dot (QD) based semiconductor qubits. We study the low-frequency charge noise by charge offset drift measurements for Si-MOS devices with intentionally implanted donors near the…
Due to presence of magnetic field gradient needed for coherent spin control, dephasing of single-electron spin qubits in silicon quantum dots is often dominated by $1/f$ charge noise. We investigate theoretically fluctuations of ground…
We present observations of background charge fluctuators near an Al-AlO_x-Al single-electron transistor on an oxidized Si substrate. The transistor design incorporates a heavily doped substrate and top gate, which allow for independent…
Transport properties of ferromagnetic/non-magnetic/ferromagnetic single electron transistors are investigated as a function of external magnetic field, temperature, bias and gate voltage. By designing the magnetic electrodes to have…
In this work we show how to calculate the equilibrium and non-equilibrium charge fluctuations in a gated normal mesoscopic conductor which is attached to one normal lead and one superconducting lead. We then consider an example where the…
Radio-frequency (rf)- operated single-electron transistors (SETs) are high-sensitivity, fast-response electrometers, which are valuable for developing new insights into single-charge dynamics. We investigate high-frequency (up to 1 MHz)…
In the "flopping-mode" regime of electron spin resonance, a single electron confined in a double quantum dot is electrically driven in the presence of a magnetic field gradient. The increased dipole moment of the charge in the flopping mode…
Electron spins in silicon have long coherence times and are a promising qubit platform. However, electric field noise in semiconductors poses a challenge for most single- and multi-qubit operations in quantum-dot spin qubits. Here, we…
We incorporate an Al-AlO_x-Al single-electron transistor as the gate of a narrow (~100 nm) metal-oxide-semiconductor field-effect transistor (MOSFET). Near the MOSFET channel conductance threshold, we observe oscillations in the conductance…
We present a new fully self-aligned single-electron memory with a single pair of nano floating gates, made of different materials (Si and Ge). The energy barrier that prevents stored charge leakage is induced not only by quantum effects but…
The scalability of spin qubit devices is conditioned by qubit-to-qubit variability. Disorder in the host materials indeed affects the wave functions of the confined carriers, which leads to variations in their charge and spin properties.…
We report on measurements of low frequency noise in a single electron transistor from a few Hz up to 10 MHz. Measurements were done for different bias and gate voltages, which allows us to separate noise contributions from different noise…
Nanofabricated metal gate electrodes are commonly used to confine and control electrons in electrostatically defined quantum dots. However, these same gates impart strain-induced potential fluctuations that can potentially impair device…
We report on a quantum dot device design that combines the low disorder properties of undoped SiGe heterostructure materials with an overlapping gate stack in which each electrostatic gate has a dominant and unique function -- control of…
Metal-oxide-semiconductor field-effect transistors (MOSFET's) using atomic-layer-deposited (ALD) Al$_2$O$_3$ as the gate dielectric are fabricated on the Si/Si$_{1-x}$Ge$_x$ heterostructures. The low-temperature carrier density of a…
We report measurements of charge configurations and charge transfer dynamics in a hybrid single-electron box composed of aluminum and copper. We used two single-electron transistors (SETs) to simultaneously read out different parts of the…
We measure the interdot charge relaxation time T_1 of a single electron trapped in an accumulation mode Si/SiGe double quantum dot. The energy level structure of the charge qubit is determined using photon assisted tunneling, which reveals…
We theoretically investigate quantum fluctuation of charge between even and odd states of a normal-superconducting-normal single-electron tunneling transistor. It is shown that due to the superconducting gap, the charge fluctuation in the…