Light Emission From Inelastic Tunneling — LEIT

Abstract

It has been shown that inelastic tunneling excitation of surface plasmon modes can result in light emission when electrodes are properly prepared. The light emission establishes a fundamental quantum relationship between the maximum optic frequency and the applied voltage. Such a process can be used as a basis for spectroscopy when modulation-derivative techniques are used. The derivative method is very similar to that used in IETS except it is a second derivative of a photo detection current that is measured. We term this LEIT spectroscopy (light emission by inelastic tunneling). We will discuss the physical processes underlying the LEIT effect as well as possible applications. Some of the key factors of this light source are: 1) the precision of the relationship between voltage and maximum optical frequency; 2) mechanics for coupling out light for excited surface plasmon modes; 3) the optical range over which such sources can be operated.