A Valleytronic Diamond Transistor: Electrostatic Control of Valley Currents and Charge-State Manipulation of NV Centers

Abstract

The valley degree of freedom in many-valley semiconductors provides a new paradigm for storing and processing information in valleytronic and quantum-computing applications. Achieving practical devices requires all-electric control of long-lived valley-polarized states, without the use of strong external magnetic fields. Because of the extreme strength of the carbon–carbon bond, diamond possesses exceptionally stable valley states that provide a useful platform for valleytronic devices. Using ultrapure single-crystalline diamond, we demonstrate electrostatic control of valley currents in a dual-gate field-effect transistor, where the electrons are generated with a short ultraviolet pulse. The charge current and the valley current measured at the receiving electrodes are controlled separately by varying the gate voltages. We propose a model to interpret experimental data, based on drift-diffusion equations coupled through rate terms, with the rates computed by microscopic Monte Carlo simulations. As an application, we demonstrate valley-current charge-state modulation of nitrogen-vacancy centers.

Non‐Volatile Photo‐Switch Using a Diamond pn Junction

“…The long valley-polarization relaxation times of electrons make diamond a good candidate for use as valleytronics transistor. [3,4] Diamond takes also advantage of point defects, like nitrogen vacancy centers, for applications in quantum sensing, [5] quantum communication [6] or spinbased photonic quantum technologies. [7] Finally, its bio-compatibility offers the possibility of integrating diamond electronics into the human body.…”

Schottky type photodiodes with organic Co‐complex and Cd‐complex interlayers

“…[29][30][31] Sometimes an insulator or metal oxide interlayer can be inserted between metal and semiconductor to control charge conduction and stop leakage current or electrostatic charge generation. [32][33][34][35] Furthermore, this interfacial material can also increase effectivity of the metal-semiconductor contacts due to adjustable barrier height and passivate dangling bonds. [36][37][38][39] The synthesized MOFs or metal complexes can be used in the metal semiconductor contacts as an interfacial layer to obtain electronic devices.…”

Semiconductor Bloch equation analysis of optical Stark and Bloch-Siegert shifts in monolayers WSe$_2$ and MoS$_2$

“…The carriers with low effective mass in the direction of the applied field gain higher kinetic energy than heavier quasiparticles and therefore the probability of intervalley scattering from light to heavy valleys is larger than in opposite direction. This mechanism allows to generate valley polarized electron population from the initial isotropic distribution in momentum space in diamond 9,10 .…”