Thermo-optical spectroscopy: Detection by the ’’mirage effect’’

Abstract

A new thermo-optical method based on the sensitive detection of thermal gradients adjacent to heated sample surfaces is described. Room- and low-temperature experiments were performed using this technique, and its advantages over different methods are discussed.

Parametric study of the frequency-domain thermoreflectance technique

“…Photothermal techniques include photothermal displacement, 7 photothermal beam deflection (or "mirage"), 8 photothermal radiometry (PTR), 9 and photothermal reflectance (or thermoreflectance). [10][11][12][13] Thermoreflectance techniques may be distinguished as one of the two measurement types: time-domain and frequencydomain measurements.…”

Time Resolved Optical Detection of Electron Loss and Migration in CdS

“…This paper presents Optical Beam Deflection (OBD) studies of CdS using an electron beam as an excitation source and a subbandgap optical beam as a probe to study electron transport mechanisms resulting from electron loss in the specimen. The OBD method monitors the deflection of the probe beam produced by an index of refraction gradient field in the sample induced by the exciting beam [2,3]. Beam deflection measurements were made as a function of depth in both the time and frequency domains.…”

Optical Second Harmonic Generation for Surface Studies

“…This suggests that for a > 1/3, a new site may have appeared for CO adsorption on Rh. Indeed, previous studies [15] have shown that CO adsorbs to Rh on the top sites if 6 < 1/3, and on both the top sites and the bridge sites if 6 > 113. Using the model of noninteracting adsorption sites, we can again-write the surface nonlinear sus-ceptibili ty as for6.s_113 A + B/36s + C(6 -1/3)/6s for 1/3 .S.…”

“…Using the model of noninteracting adsorption sites, we can again-write the surface nonlinear sus-ceptibili ty as for6.s_113 A + B/36s + C(6 -1/3)/6s for 1/3 .S. 6 .S. 314.…”

“…It is found that laser-induced fluorescence or resonant ionization can be used to probe angular, velocity, and internal energy distributions of molecules scattered or desorbed from a surface [2]. Coherent Raman spectroscopy [3], laser-induced desorption [4], photoacoustic spectroscopy [5], and photothermal deflection spectroscopy [6] can be used to study surface states and molecular vibrations of adsorbates. Lately, we have shown that surface second harmonic generation (SHG) is also an effective tool for surface studies [7].…”