Precise Test for the Casimir Effect using Roberval's Balance

1993 Fiscal Year Final Research Report Summary

• Project/Area Number: 04452020
• Research Category: Grant-in-Aid for General Scientific Research (B)
• Allocation Type: Single-year Grants
• Research Field: 核・宇宙線・素粒子
• Research Institution: The University of Tokyo
• Principal Investigator: YOSHIDA Tetsuya The University of Tokyo, Faculty of Science, Research Associate, 理学部, 助手 (50222394)
• Project Period (FY): 1992 – 1993
• Keywords: Casimir effect / Roberval's Balance / 平行金属極板 / 極板間絶対距離

Research Abstract

In order to test the Casimir effect, the force between two metal plates should be directly measured using the electric Roberval's balance. The detector was developed as follows ;
(1) Metal plates were fabricated by gold vacuum evaporation onto quartz plates. Though the surface of the plates should be clean enough to place two plates closer than one micron, some clusters larger than several microns were found on the surface of the plates. The clean-up method of the quartz plates were investigated, and the conditions of the vacuum evaporation were changed to avoid the gold clusters.
(2) Interferometer was used to measure absolute distance between two metal plates. The accuracy of the absolute distance of 50 nm was achieved. Using the laser interferometers and the electric actuator, the distance between two metal plates can be controlled in the accuracy less than 10 nm.
(3) To avoid the vibration of the metal plates, the electric Roberval's balance was put on the air cushion. Convection of the air inside the detector was also controlled to reduce the vibration of the metal plates.
Some technical difficulties still exists in the fabrication of the metal plates, so the development of the detector is continued.