Fig. 2: High-temperature superconducting diode effect (SDE) at zero magnetic field in BSCCO flake device s1.

a V-I curves measured by ramping the current from negative to positive (positive sweep, orange line) and from positive to negative (negative sweep, purple line) at 53 K. The black dashed line represents zero voltage. b V-I curves containing 0–P (sweeping from zero to positive, orange line) and 0–N (sweeping from zero to negative, purple line) branches at 53 K, showing asymmetric critical current along opposite directions, namely \({I}_{{{{\rm{c}}}}+}\) and \({{|I}}_{{{{\rm{c}}}}-}|\). c Half-wave rectification measured at 53 K under zero magnetic field, showing an alternating switching between superconducting and resistive state depending on the direction of the current. The amplitude of the excitation current is 38 \({{{\rm{\mu }}}}{{{\rm{A}}}}\) and the frequency is 0.017 Hz. The red dashed lines represent the value of zero. d Rectification response observed in 200 cycles (over 3 h), illustrating high stability of the SDE. e \({I}_{{{{\rm{c}}}}+}\) and \({{|I}}_{{{{\rm{c}}}}-}|\) obtained from the 0–P and 0–N branches as a function of temperature at zero magnetic field. The diode effect vanishes at 75 K, which is very close to \({T}_{{{\rm{c}}}}^{{{\rm{zero}}}}\,\)(75.5 K). f Temperature dependence of the diode efficiency \(\eta\). The efficiency reaches its maximum around 22% at 53 K and becomes zero at 75 K.