A superconducting phase in laser-ion doped diamond

We present results on boron-doped diamond samples where we observe a superconducting phase at transition temperatures in the 0.5 K range via laser-ion doping. Achieving superconductivity in boron-doped diamonds by ion implantation has previously been impeded by damage formed when using conventional ion implantation methods. We observe boron concentrations of up to ~10^22/cm^3 after directing a petawatt laser-driven boron ion pulse onto diamond samples. The resulting high boron concentration leads to the emergence of a superconducting phase, characterized by critical transition temperatures, Tc, of ~0.5 K. Tc value are dependent on detailed laser-ion doping conditions. Tc values obtained to date by laser-ion doping are much lower than Tc values that have been observed in diamonds that had been doped with boron during crystal growth (up to ~10 K). Our results show that intense ion pulses from laser-acceleration can heat, excite and dope semiconductors to levels that have been out of reach for more conventional methods. We will discuss strategies for further process optimization to reach higher Tc values that have been predicted for highly boron doped diamond and integration of superconducting structures with quantum emitters [1, 2].