Superconductivity in diamond

Diamond is an electrical insulator well known for its exceptional hardness. It also conducts heat even more effectively than copper, and can withstand very high electric fields. With these physical properties, diamond is attractive for electronic applications, particularly when charge carriers are introduced (by chemical doping) into the system. Boron has one less electron than carbon and, because of its small atomic radius, boron is relatively easily incorporated into diamond; as boron acts as a charge acceptor, the resulting diamond is effectively hole-doped. Here we report the discovery of superconductivity in boron-doped diamond synthesized at high pressure (nearly 100,000 atmospheres) and temperature (2,500–2,800 K). Electrical resistivity, magnetic susceptibility, specific heat and field-dependent resistance measurements show that boron-doped diamond is a bulk, type-II superconductor below the superconducting transition temperature Tc ≈ 4 K; superconductivity survives in a magnetic field up to Hc2(0) ≥ 3.5 T. The discovery of superconductivity in diamond-structured carbon suggests that Si and Ge, which also form in the diamond structure, may similarly exhibit superconductivity under the appropriate conditions.

[1]  A. Larkin,et al.  Possibility of superconductivity in semiconductors , 1962 .

[2]  C. P. Bean.  Magnetization of hard superconductors , 1962 .

[3]  C. Gorter,et al.  Progress in low temperature physics , 1964 .

[4]  M. Cohen.  SUPERCONDUCTIVITY IN MANY-VALLEY SEMICONDUCTORS AND IN SEMIMETALS , 1964 .

[5]  E. Helfand,et al.  Temperature and Purity Dependence of the Superconducting Critical Field, H c 2 . III. Electron Spin and Spin-Orbit Effects , 1966 .

[6]  W. L. Mcmillan.  TRANSITION TEMPERATURE OF STRONG-COUPLED SUPERCONDUCTORS. , 1968 .

[7]  A. T. Collins,et al.  Impurity conduction in synthetic semiconducting diamond , 1970 .

[8]  On the Transition Temperature of Strongly Coupled Superconductors , 1970 .

[9]  Y. Takada,et al.  Superconductivity from an Insulator , 1990 .

[10]  L. Berger.  Motion of a magnetic domain wall traversed by fast‐rising current pulses , 1992 .

[11]  J. Field.  The Properties of natural and synthetic diamond , 1992 .

[12]  S. Romani,et al.  Charge transport in heavily B‐doped polycrystalline diamond films , 1994 .

[13]  L. Berger,et al.  Current‐induced displacements of Bloch walls in Ni‐Fe films of thickness 120–740 nm , 1994 .

[14]  Yamanaka,et al.  Superconductivity in the silicon clathrate compound (Na,Ba)xSi46. , 1995, Physical review letters.

[15]  M. Geis,et al.  Electron field emission from diamond and other carbon materials after H2, O2, and Cs treatment , 1995 .

[16]  O. Weis,et al.  Boron-Doped Homoepitaxial Diamond Layers: Fabrication, Characterization, and Electronic Applications , 1996 .

[17]  S. T. Lee,et al.  Characterization of heavily boron-doped diamond films , 1996 .

[18]  A. Deneuville,et al.  Variation of the cell parameter of polycrystalline boron doped diamond films , 1997 .

[19]  From semiconductors to superconductors: a simple model for pseudogaps , 1999, cond-mat/9902273.

[20]  D. K. Young,et al.  Electrical spin injection in a ferromagnetic semiconductor heterostructure , 1999, Nature.

[21]  H. Ohno,et al.  Electric-field control of ferromagnetism , 2000, Nature.

[22]  H. Ohno,et al.  Zener model description of ferromagnetism in zinc-blende magnetic semiconductors , 2000, Science.

[23]  P. May.  Diamond thin films: a 21st-century material , 2000, Philosophical Transactions of the Royal Society of London. Series A: Mathematical, Physical and Engineering Sciences.

[24]  M. Baenitz,et al.  Superconductivity in the filled cage compounds Ba6Ge25 and Ba4Na2Ge25. , 2001, Physical review letters.

[25]  H. Ohno,et al.  Hole-mediated ferromagnetism in tetrahedrally coordinated semiconductors , 2000, cond-mat/0007190.

[26]  H. Mao,et al.  Superconductivity in Boron , 2001, Science.

[27]  Rafi Kalish,et al.  The search for donors in diamond , 2001 .

[28]  J. Coey,et al.  Domain walls in ferromagnetic nanoconstriction , 2002 .

[29]  H. Ohno,et al.  Effect of low-temperature annealing on (Ga,Mn)As trilayer structures , 2003 .

[30]  J. Butler,et al.  Shallow donors with high n-type electrical conductivity in homoepitaxial deuterated boron-doped diamond layers , 2003, Nature materials.

[31]  Michael E. Flatté,et al.  Theory of semiconductor magnetic bipolar transistors , 2003 .

[32]  D D Awschalom,et al.  Giant planar Hall effect in epitaxial (Ga,Mn)as devices. , 2003, Physical review letters.

[33]  V. Zayets,et al.  Room-temperature ferromagnetism in a II-VI diluted magnetic semiconductor Zn(1-x)Cr(x)Te. , 2003, Physical review letters.

[34]  M. Amann,et al.  Fabrication of in-plane gate transistors on hydrogenated diamond surfaces , 2003 .

[35]  H. Ohno,et al.  Electrical Manipulation of Magnetization Reversal in a Ferromagnetic Semiconductor , 2003, Science.

[36]  David P. Norton,et al.  Wide band gap ferromagnetic semiconductors and oxides , 2003 .

[37]  G. Tatara,et al.  Theory of current-driven domain wall motion: spin transfer versus momentum transfer. , 2004, Physical review letters.