The 2022 Nobel prize celebrates the detection of entanglement between two photons. Quantum spin liquids (QSLs) are long-range entangled states of matter of billions of interacting qubits or spins that develop in a Mott insulator. The fate of the interacting spins can progress along two paths as the temperature is lowered: the spins can undergo long range ordering, spontaneously breaking the continuous symmetries, leading to a magnetic phase; or the spins can remain disordered but get quantum mechanically entangled with long range patterns of many-body entanglement in the resultant QSL. The possibility of obtaining QSL phases is enhanced by having a low spin and enhanced quantum fluctuations, and frustration arising from the lattice geometry and/or competing spin-spin interactions. Remarkably QSLs harbor fractionalized excitations rather than the conventional spin waves of ordered magnets that carry integer units of angular momentum. In my talk I will identify detectable signa tures of these fractionalized excitations in experiments using light and neutrons. These fractionalized excitations are promising candidates to create logical qubits for quantum computation.
Nandini Trivedi is a Professor of Physics and a Distinguished Professor of the College of Arts and Sciences?at the Ohio State University. Trivedi got her undergraduate degree from the Indian Institute of Technology, Delhi and?a Ph.D in physics in 1987 from Cornell University. After post-doctoral research at University of Illinois at Urbana-Champaign and State University of New York, Stony Brook, she joined Argonne National Laboratory as a staff scientist. In 1995 she joined the faculty of the Tata Institute of Fundamental Research, Mumbai. Since 2004 she has been a professor of physics at the Ohio State University. Trivedi’s research is in understanding emergent phases in quantum matter due to strong correlations and topology.