On-Chip Strain Enhanced Superconductivity in 1T'-MoTe₂

Two-dimensional transition metal ditellurides have been found to have unique electronic/structural phase transitions with respect to strain. Bulk Weyl semimetal 1T'-MoTe₂ has been shown to exhibit enhanced superconductivity from the nominal value of 100 mK up to 7 K under applied hydrostatic pressure. In this work, we explore the use of on-chip thin film stress capping layers to achieve the same effect from in-plane strain on exfoliated 1T'-MoTe₂. These stress capping layers are analogous to the SiN_x capping layers used in industrial strained silicon processes. We examine 1T'-MoTe₂ channels under various thin film stressors and observe superconducting onsets at temperatures as high as 4 K. Devices are sensitive to both geometry and stressor layer composition. Control devices eliminate the potential of this effect arising from defect formation or unintended doping. Challenges related to low-temperature thin film strain transfer, and thermal matching of the stressor layers will be explored. Upon further optimization and standardization, this technique can be used to explore the superconducting phase diagram of MoTe₂ with respect to strain, temperature, and thickness.