In this article, we present a nanoelectromechanical system (NEMS) designed to detect changes in the Casimir energy. The Casimir effect is a result of the appearance of quantum fluctuations in an electromagnetic vacuum. Previous experiments have used nano- or microscale parallel plate capacitors to detect the Casimir force by measuring the small attractive force these fluctuations exert between the two surfaces. In this new set of experiments, we aim to directly detect the shifts in the Casimir energy in a vacuum due to the presence of the metallic parallel plates, one of which is a superconductor. A change in the Casimir energy of this configuration is predicted to shift the superconducting transition temperature (
Logic switches enabled by nanoelectromechanical systems (NEMS) offer abrupt on/off‐state transition with zero off‐state leakage and minimal subthreshold swing, making them uniquely suited for enhancing mainstream electronics in a range of applications, such as power gating, high‐temperature and high‐voltage logic, and ultralow‐power circuits requiring zero standby leakage. As NEMS switches are scaled with genuinely nanoscale gaps and contacts, quantum mechanical electrodynamic force (EDF) takes an important role and may be the ultimate cause of the plaguing problem of stiction. Here, combined with experiments on three‐terminal silicon carbide (SiC) NEMS switches, a theoretical investigation is performed to elucidate the origin of EDF and Casimir effect leading to stiction, and to develop a stiction‐mitigation design. The EDF calculation with full Lifshitz formula using the actual material and device parameters is provided. Finite element modeling and analytical calculations demonstrate that EDF becomes dominant over elastic restoring force in such SiC NEMS when the switching gap shrinks to a few nanometers, leading to irreversible stiction at contact. Artificially corrugated contact surfaces are designed to reduce the contact area and the EDF, thus evading stiction. This rational
- PAR ID:
- 10454707
- Publisher / Repository:
- Wiley Blackwell (John Wiley & Sons)
- Date Published:
- Journal Name:
- Small
- Volume:
- 16
- Issue:
- 51
- ISSN:
- 1613-6810
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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