Measurement of the infrared transmission spectrum of synchrotron radiation through a superconducting YBa2Cu3O7−δ film

This paper presents results of measurements of the infrared transmission spectrum of synchrotron radiation through a YBa2Cu3O7−δ film on a MgO substrate at a temperature T = 20 K. The transition temperature of the superconducting state of the film is Tc = 80 K. Through the film the synchrotron radiation from a pulsed electron accumulator is transmitted at the power maximum being rebuilt from 100 μm to 10 μm during every formation cycle of the electron ring pulse. Due to the spectrum evolution, the signal of the detector which registers the transmission through the sample is related to the transmitting ability of the sample, the sensitivity of the detector and the synchrotron radiation spectrum via an integral equation. The best agreement with the experimental results is achieved for a value of the energy gap 2Δ = 20 meV which corresponds to 2ΔkTc = 2.9 at T = 20 K.