Applications of High-Pressure Electrical Transport in Exploring Quantum States of Matter — The A1 Experimental Station at the Huairou Synergetic Extreme Condition User Facility

Synergetic Extreme Conditions, including high pressure, ultra-low temperature, and strong magnetic fields, provide powerful experimental approaches for exploring novel quantum states of matter and tuning quantum phase transitions. This paper introduces the A1 diamond anvil cell (DAC) experimental station at the Huairou Synergetic Extreme Condition User Facility (SECUF). Designed for high-pressure electrical transport studies under extreme conditions, this platform integrates six parallel miniature high-pressure cells, enabling electrical transport measurements on multiple samples under pressures exceeding 100 GPa, temperatures down to 500 mK, and magnetic fields up to 14 T. The paper systematically describes the instrument design, experimental procedures, and capabilities of the A1 station for conducting quantum material research under combined extreme environments and summarizes its representative scientific achievements. Key advances enabled by this platform include the discovery of new chromium-based superconductors, reproducible pressure-induced superconductivity in La₃Ni₂O₇, structural reconstruction and superconducting evolution in layered quantum materials, as well as the manipulation of superconducting electronic structures and correlated magnetic states under high pressure. Furthermore, by integrating complementary measurement techniques such as high-pressure low-temperature calorimetry, the A1 station has expanded investigations into complex spin states and other correlated quantum phenomena. These studies demonstrate the important role of high-pressure electrical transport and multimodal extreme-condition techniques in discovering novel quantum phenomena, understanding the evolution of quantum states, and exploring correlation effects in quantum materials. Finally, this paper discusses future developments of the A1 station, including multiparameter quantum-state control, in situ multimodal characterization, and the exploration of emerging quantum materials.