Electrically switchable Casimir forces using transparent conductive oxides

Abstract

Casimir forces between charge-neutral bodies originate from quantum vacuum fluctuations of electromagnetic fields, which exhibit a critical dependence on material's electromagnetic properties. Over the years, in-situ modulation of material's optical properties has been enabled through various means and has been widely exploited in a plethora of applications such as electro-optical modulation, transient color generation, bio- or chemical sensing, etc. Yet Casimir force modulation has been hindered by difficulty in achieving high modulation signals due to the broadband nature of the Casimir interaction. Here we propose and investigate two configurations that allow for in-situ modulation of Casimir forces through electrical gating of a metal-insulator-semiconductor (MIS) junction comprised of transparent conductive oxide (TCO) materials. By switching the gate voltage on and off, a force modulation of > 400 pN is predicted due to substantive charge carrier accumulation in the TCO layer, which can be easily measured using state-of-the-art force measurement techniques in an atomic force microscope (AFM). We further examine the influence of the oxide layer thickness on the force modulation, suggesting the importance of the fine control of the oxide layer deposition. Our work provides a promising pathway for modulating the Casimir effect in-situ with experimentally measurable force contrast.

References in corpus (13)

• Measurement of the Casimir force between a gold sphere and silicon surface with nanoscale trench arrays
• Control of the Casimir force by the modification of dielectric properties with light
• Halving the Casimir force with conductive oxides
• Demonstration of optically modulated dispersion forces
• Influence of random roughness on the Casimir force at small separations
• Demonstration of the difference Casimir force for samples with different charge carrier densities
• Experimental test for the conductivity properties from the Casimir force between metal and semiconductor
• Precision measurement of the Casimir-Lifshitz force in a fluid
• Measurements of the Casimir-Lifshitz force in fluids: the effect of electrostatic forces and Debye screening
• Casimir Force Phase Transitions in the Graphene Family
• Experimental approaches to the difference in the Casimir force through the varying optical properties of boundary surface
• Transition from Casimir to van der Waals force between macroscopic bodies
• Design of a Casimir-driven parametric amplifier