Research-Topic: Quantum coherence measurement of spins on insulators
About us: The IBS Center for Quantum Nanoscience (QNS) is a basic research center located in the heart Seoul, South Korea. Our working language is English, 50% of our researchers come from outside of Korea, and 55% of our researchers are women. QNS is laying the foundation for future quantum technologies by exploring the use of quantum behavior atom by atom with highest precision. We focus on the fabrication and exploration of quantum nanostructures while aiming at achieving full control over the quantum states of the constituent atoms and molecules. QNS has become a leading center in the field of quantum-coherent nanoscience by filling our world-class facility with ground-breaking tools and inquisitive minds immersed in a culture of exploration.
About the Project: Spins on thin insulating films can be studied with STM, which requires a tunnel current to flow between tip and sample. Hence, the insulating films have to atomically thin typically between one and four layers thick. However, the key spin properties of energy relaxation time (T1) and quantum coherence time (T2) are strongly reduced through the presence of the metal electrons.
We are aiming to work with spin qubits on thick insulating films or on bulk insulators. Hence, we need a new research tool to measure individual spins. The atomic force microscope (AFM) is a cousin of the STM, which measures the force between a tip and the sample. We use a q-plus force sensor with a conducting tip. This allows us simultaneous operation of STM and AFM. In order to measure the magnetic properties of spin-qubits, we rely on the spin-dependent forces between a magnetic tip and the qubits on the insulating surface.