Ramakanta Chapai1,Gordon Peterson1,Matthew Smylie1,2,Xinglong Chen1,Jidong Samuel Jiang1,David Graf3,Wai-Kwong Kwok1,John Mitchell1,Ulrich Welp1
Argonne National Laboratory1,Hofstra University2,National High Magnetic Field Laboratory3
Ramakanta Chapai1,Gordon Peterson1,Matthew Smylie1,2,Xinglong Chen1,Jidong Samuel Jiang1,David Graf3,Wai-Kwong Kwok1,John Mitchell1,Ulrich Welp1
Argonne National Laboratory1,Hofstra University2,National High Magnetic Field Laboratory3
The Parkerite-type transition-metal chalcogenides Pd<sub>3</sub>Bi<sub>2</sub>Se<sub>2 </sub>is a superconductor with <i>T</i><sub>c</sub> ~ 0.8 K. Recently, a non-zero Z<sub>2</sub> topological index has been predicted in Pd<sub>3</sub>Bi<sub>2</sub>Se<sub>2</sub>, and subsequently unusual magneto-transport attributed to two-dimensional fermions is reported. By measuring the field dependence of magnetic torque in bulk single crystalline Pd<sub>3</sub>Bi<sub>2</sub>Se<sub>2</sub> we observe de Haas-van Alphen (dHvA) oscillations. Through the analysis of the dHvA oscillations with <i>H</i> || <i>c</i>, three frequencies are identified: <i>F</i><sub>α</sub> = 150 T, <i>F</i><sub>β</sub> = 471 T and <i>Fγ</i> = 979 T with the low frequency dominating the spectrum. The Lifshitz-Kosevich analysis yields a small effective mass (0.11<i>m</i><sub>0</sub>) and nontrivial Berry phase (~π) for the dominant orbit, indicating nontrivial topology. The presence of nontrivial topology in a superconducting system makes Pd<sub>3</sub>Bi<sub>2</sub>Se<sub>2 </sub>a promising candidate to explore topological superconductivity.