Turning ZrTe5 into semiconductor through atomic intercalation

TL;DR

This paper demonstrates that potassium intercalation into ZrTe5 via liquid ammonia induces a transition from semimetal to semiconductor, suppressing resistance anomalies and reversing Hall resistance sign, likely due to lattice expansion and band gap increase.

Contribution

It introduces a novel method of atomic intercalation to control the electronic phase of ZrTe5, achieving a semimetal to semiconductor transition.

Findings

Semimetal to semiconductor transition observed

Resistance anomaly suppressed with potassium intercalation

Hall resistance sign reversal consistent with phase change

Abstract

In this work, we use the liquid ammonia method to successfully intercalate potassium atoms into ZrTe5 single crystal, and find a transition from semimetal to semiconductor at low temperature in the intercalated ZrTe5. The resistance anomalous peak is gradually suppressed and finally disappears with increasing potassium concentration. Whilst, the according sign reversal is always observed in the Hall resistance measurement. We tentatively attribute the semimetal-semiconductor transition to the lattice expansion induced by atomic intercalation and thereby a larger energy band gap.