An object of the invention is to provide: an MgB.sub.2 superconducting thin-film wire that exhibits excellent J.sub.c characteristics even under a 20 K magnetic field; and a method for producing thereof. The MgB.sub.2 superconducting thin-film wire includes a long substrate and an MgB.sub.2 thin film formed on the long substrate. The MgB.sub.2 thin film has a microtexture such that MgB.sub.2 columnar crystal grains stand densely together on the surface of the long substrate, and has T.sub.c of 30 K or higher. In grain boundary regions of the MgB.sub.2 columnar crystal grains, a predetermined transition metal element is dispersed and segregated. The predetermined transition metal element is an element having a body-centered cubic lattice structure.

An object of the invention is to provide: an MgB.sub.2 superconducting thin-film wire that exhibits excellent J.sub.c characteristics even under a 20 K magnetic field; and a method for producing thereof. The MgB.sub.2 superconducting thin-film wire includes a long substrate and an MgB.sub.2 thin film formed on the long substrate. The MgB.sub.2 thin film has a microtexture such that MgB.sub.2 columnar crystal grains stand densely together on the surface of the long substrate, and has T.sub.c of 30 K or higher. In grain boundary regions of the MgB.sub.2 columnar crystal grains, a predetermined transition metal element is dispersed and segregated. The predetermined transition metal element is an element having a body-centered cubic lattice structure.

A method for manufacturing diamond substrate of using source gas containing hydrocarbon gas and hydrogen gas to form diamond crystal on an underlying substrate by CVD method, to form a diamond crystal layer having nitrogen-vacancy centers in at least part of the diamond crystal, nitrogen or nitride gas is mixed in the source gas, wherein the source gas is: 0.005 volume % or more and 6.000 volume % or less of the hydrocarbon gas; 93.500 volume % or more and less than 99.995 volume % of the hydrogen gas; and 5.0×10.sup.−5 volume % or more and 5.0×10.sup.−1 volume % or less of the nitrogen gas or the nitride gas, and the diamond crystal layer having the nitrogen-vacancy centers is formed. A method for manufacturing a diamond substrate to form an underlying substrate, a diamond crystal having a dense nitrogen-vacancy centers (NVCs) with an orientation of NV axis by performing the CVD.

A method for manufacturing diamond substrate of using source gas containing hydrocarbon gas and hydrogen gas to form diamond crystal on an underlying substrate by CVD method, to form a diamond crystal layer having nitrogen-vacancy centers in at least part of the diamond crystal, nitrogen or nitride gas is mixed in the source gas, wherein the source gas is: 0.005 volume % or more and 6.000 volume % or less of the hydrocarbon gas; 93.500 volume % or more and less than 99.995 volume % of the hydrogen gas; and 5.0×10.sup.−5 volume % or more and 5.0×10.sup.−1 volume % or less of the nitrogen gas or the nitride gas, and the diamond crystal layer having the nitrogen-vacancy centers is formed. A method for manufacturing a diamond substrate to form an underlying substrate, a diamond crystal having a dense nitrogen-vacancy centers (NVCs) with an orientation of NV axis by performing the CVD.

A magnetic material is constituted of a ferromagnetic or ferrimagnetic insulator in a double perovskite structure of Sr.sub.3-xA.sub.xOs.sub.1-yB.sub.yO.sub.6 (0.5≤x≤0.5, −0.5≤y≤0.5). A is an alkali metal or alkaline earth metal atom, and B is a transition metal atom, alkali metal atom, or alkaline earth metal atom). The insulator may be Sr.sub.3OsO.sub.6, where x=y=0 in the above formula. Sr.sub.3OsO.sub.6 is formed to have a cubic crystal structure where strontium atoms, osmium atoms, and oxygen atoms are arranged at lattice points.

A magnetic material is constituted of a ferromagnetic or ferrimagnetic insulator in a double perovskite structure of Sr.sub.3-xA.sub.xOs.sub.1-yB.sub.yO.sub.6 (0.5≤x≤0.5, −0.5≤y≤0.5). A is an alkali metal or alkaline earth metal atom, and B is a transition metal atom, alkali metal atom, or alkaline earth metal atom). The insulator may be Sr.sub.3OsO.sub.6, where x=y=0 in the above formula. Sr.sub.3OsO.sub.6 is formed to have a cubic crystal structure where strontium atoms, osmium atoms, and oxygen atoms are arranged at lattice points.

An asymmetric pigment including a first Fabry-Perot structure; and a second Fabry-Perot structure; wherein the first Fabry-Perot structure and the second Fabry-Perot structure have a similar hue angle within +/−45 degrees is disclosed. Other asymmetric pigments are also disclosed as well as methods of making the disclosed pigments.

An asymmetric pigment including a first Fabry-Perot structure; and a second Fabry-Perot structure; wherein the first Fabry-Perot structure and the second Fabry-Perot structure have a similar hue angle within +/−45 degrees is disclosed. Other asymmetric pigments are also disclosed as well as methods of making the disclosed pigments.

A method for manufacturing diamond substrate of using source gas containing hydrocarbon gas and hydrogen gas to form diamond crystal on an underlying substrate by CVD method, to form a diamond crystal layer having nitrogen-vacancy centers in at least part of the diamond crystal, nitrogen or nitride gas is mixed in the source gas, wherein the source gas is: 0.005 volume % or more and 6.000 volume % or less of the hydrocarbon gas; 93.500 volume % or more and less than 99.995 volume % of the hydrogen gas; and 5.0×10.sup.−5 volume % or more and 5.0×10.sup.−1 volume % or less of the nitrogen gas or the nitride gas, and the diamond crystal layer having the nitrogen-vacancy centers is formed. A method for manufacturing a diamond substrate to form an underlying substrate, a diamond crystal having a dense nitrogen-vacancy centers (NVCs) with an orientation of NV axis by performing the CVD.

An asymmetric pigment including a first Fabry-Perot structure; and a second Fabry-Perot structure; wherein the first Fabry-Perot structure and the second Fabry-Perot structure have a similar hue angle within +/45 degrees is disclosed. Other asymmetric pigments are also disclosed as well as methods of making the disclosed pigments.