Why are low temperatures used in scanning tunneling microscope studies of superconductors?

In scanning tunneling microscopy (STM) studies of superconductors, low temperatures are essential because superconductivity is a phenomenon that only occurs below a material's specific transition temperature.12

Beyond simply maintaining the superconducting state, low temperatures are critical for accurately measuring the energy gap ($\Delta$). In tunneling experiments, researchers aim to determine the energy gap by observing the current-voltage characteristics of a junction. For these measurements to be precise, the electrons must derive their energy from the applied voltage rather than from thermal excitation. At higher temperatures, thermal energy can excite electrons across the energy gap, which obscures the measurement and complicates the interpretation of the superconducting state. By operating at temperatures significantly below the transition temperature, researchers ensure that the energy gap is well-defined and that the tunneling current reflects the underlying quantum mechanical properties of the superconductor rather than thermal noise.34