Method for measuring the resistive transition and critical current in superconductors using pulsed current

A method for measuring the intragranular and intergranular critical current of a granular superconductive material, comprising the steps of:

• conducting a substantially rectangular electronic pulse through said material so as to conduct a current through said material such that when said intergranular critical current of said material is exceeded, any grains present in said material are in a superconducting state when said current level is below said intragranular critical current, said material having a critical temperature;
• measuring said current through said material while conducting said pulse;
• measuring a voltage difference across said material while conducting said pulse;
• determining said intergranular critical current through said material by discerning a non-zero voltage difference across said material and contemporaneously measuring said current;
• and
• determining said intragranular critical current through said material by varying said current to discern a current level at which an electrical resistance of said material increases to that of a non-superconducting state as said grains of said material transition from said superconducting to said non-superconducting state.

A method for measuring the intergranular critical current of a granular superconductive material, comprising the steps of:

• conducting a substantially rectangular electronic pulse through said material, having a critical temperature, in order to conduct a current through said material such that when said intergranular critical current of said material is exceeded, any grains present in said material are in a superconducting state;
• measuring a voltage difference across said material while conducting said pulse;
• determining said intergranular critical current through said material by discerning a non-zero voltage difference across said material and contemporaneously measuring said current
• allowing said current to vary;
• and
• maintaining the temperature of said material at a constant temperature below said critical temperature.

A method for measuring the intergranular critical current of a granular superconductive material, comprising the steps of:

• conducting a series of substantially rectangular electronic pulses through said material, having a critical temperature, in order to conduct a current through said material such that when said intergranular critical current of said material is exceeded, any grains present in said material are in a superconducting state;
• measuring said current through said material while conducting said pulse;
• measuring a voltage difference across said material while conducting said pulse;
• determining said intergranular critical current through said material by discerning a non-zero voltage difference across said material and contemporaneously measuring said current;
• allowing said current to vary;
• and
• maintaining the temperature of said material at a constant temperature below said critical temperature.

A method for measuring the critical current of a homogeneous superconductive material, comprising the steps of:

• conducting a substantially rectangular electronic pulse through said material so as to conduct a current through said material, said material having a critical temperature;
• measuring said current through said material while conducting said pulse;
• measuring a voltage difference across said material while conducting said pulse;
• determining said critical current through said material by discerning a non-zero voltage difference across said material and contemporaneously measuring said current;
• allowing said current to vary;
• and
• maintaining the temperature of said material at a constant temperature below said critical temperature.

A method for measuring the critical current of a homogeneous superconductive material, comprising the steps of:

• conducting a series of substantially rectangular electronic pulses through said material so as to conduct a current through said material, said material having a critical temperature;
• measuring said current through said material while conducting said pulse;
• measuring a voltage difference across said material while conducting said pulse;
• determining said critical current through said material by discerning a non-zero voltage difference across said material and contemporaneously measuring said current;
• allowing said current to vary;
• and
• maintaining the temperature of said material at a constant temperature below said critical temperature.