Time-Domain Terahertz Spectroscopy in High Magnetic Fields

Abstract

There are a variety of elementary and collective terahertz-frequency excitations in condensed matter whose magnetic field dependence contains significant insight into the states and dynamics of the electrons involved. Often, determining the frequency, temperature, and magnetic field dependence of the optical conductivity tensor, especially in high magnetic fields, can clarify the microscopic physics behind complex many-body behaviors of solids. While there are advanced terahertz spectroscopy techniques as well as high magnetic field generation techniques available, combination of the two has only been realized relatively recently. Here, we review the current state of terahertz time-domain spectroscopy experiments in high magnetic fields. We start with an overview of timedomain terahertz detection schemes with a special focus on how they have been incorporated into optically accessible high-field magnets. Advantages and disadvantages of different types of magnets in performing terahertz time-domain spectroscopy experiments are also discussed. Finally, we highlight some of the new fascinating physical phenomena that have been revealed by terahertz time-domain spectroscopy in high magnetic fields.

The Future of the Correlated Electron Problem

“…There are of course many other interesting applications of large fields not listed here, especially in the domain of magnetism. We need new technological developments to access even higher fields for longer periods of time, for example to study the normal state of some cuprates with a large upper critical field (YBCO, Hg1201, Bi2212, Electrical transport 6 mK (Pan et al, 2008) 200 GPa (Drozdov et al, 2015) 45 T (Fang et al, 2020) 95 T (Ramshaw et al, 2018) 400 kV/cm (McIver et al, 2020) Thermal transport 50 mK (Toews et al, 2013) 50 GPa (Hohensee et al, 2015) 45 T (Grissonnanche et al, 2014) Heat capacity 0.6 mK (Greywall, 1986) 4.4 GPa (Zheng et al, 2014) 45 T (Riggs et al, 2011) 60 T (Terashima et al, 2018) Magnetic properties 0.2 mK (Prakash et al, 2017) 20 GPa (Jackson et al, 2005) 45 T (Jaime et al, 2012) 75 T (Zuo et al, 2015) 9 et al, 2013) 74 T (Zaric et al, 2006) Raman and PL 20 mK (PL) (Hayne et al, 1999) 1 TPa (Raman) (Dubrovinskaia et al, 2016) 45 T (Raman) (Kim et al, 2013) 89 T (PL) (Crooker and Samarth, 2007) Time-domain THz 0.4 K (Curtis et al, 2016) 34.4 MPa (Zhang et al, 2017b) 25 T (Baydin et al, 2020) ∼30 T (Baydin et al, 2020) 70 MV/cm (Schubert et al, 2014) X-ray 220 mK (Suzuki et al, 2002(Suzuki et al, , 2004 1 TPa (Dubrovinskaia et al, 2016) 10 T (Paola...…”