Quantum devices, including quantum computers, superconducting systems, space-based infrared detectors, and low-temperature materials research require stable cryogenic environments at temperatures of tens of kelvin or below. As temperature decreases, however, maintaining sufficient cooling capacity and effective heat transfer becomes increasingly challenging. Conventional cryogenic refrigeration systems are often large and complex, and can involve mechanical vibrations and substantial maintenance. At TELab, we investigate compact cryogenic cooling technologies based on solid-state cooling that do not rely on the compression and expansion of fluid refrigerants. Our work focuses on low-temperature heat transport and entropy control in thermoelectric and caloric materials, with the aim of developing new materials, devices, and system-level approaches for cryogenic cooling. In the sub-kelvin and millikelvin regimes, reliance on scarce ³He in dilution refrigeration remains a key limitation. To address this challenge, TELab explores the potential of spin, orbital, and other degrees of freedom as novel entropy reservoirs beyond conventional magnetocaloric materials.