Method for the hyperpolarisation of nuclear spin in a diamond via a long-range interaction

Abstract

The invention concerns a method for the hyperpolarisation of 13C nuclear spin in a diamond, comprising an optical pumping step, in which colour centre electron spins in the diamond are optically pumped. The method further comprises a transfer step in which the polarisation of a long-lived state of the colour centre electron spins is transferred to 13C nuclear spins in the diamond via a long-range interaction.

1 .- 20 . (canceled) 
     
     
         21 . A method for hyperpolarizing a sample, comprising:
 a. placing the sample near or in contact with a diamond or a plurality of diamond particles having color centers;   b. optically polarizing the color centers;   c. transferring the polarization from the color centers to  13 C nuclear spins in the diamond or plurality of diamond particles;   d. propagating the polarization from the  13 C nuclear spins to  13 C nuclear spins in the sample;   wherein the method is performed at temperatures higher than or equal to 77K and lower than about 298K.   
     
     
         22 . The method according to  claim 21 , wherein the sample is placed in contact with the diamond or a plurality of diamond particles after the  13 C nuclear spins are already hyperpolarized. 
     
     
         23 . The method according to  claim 21 , wherein the sample is placed in contact with the diamond or plurality of diamond particles before the polarization of the  13 C nuclear spins. 
     
     
         24 . The method according to  claim 21 , wherein transferring the polarization from the color centers to the  13 C nuclear spins in the diamond or the plurality of diamond particles includes applying at least one of a microwave field or a radio frequency (RF) field. 
     
     
         25 . The method according to  claim 24 , wherein at least one of the microwave field or the RF field applied is pulsed. 
     
     
         26 . The method according to  claim 21 , wherein the polarization from the color centers is transferred to the  13 C nuclear spins in the diamond or the plurality of diamond particles via a long-range interaction while fulfilling the Harman-Hahn condition. 
     
     
         27 . The method according to  claim 26 , wherein the Hartmann-Hahn condition is achieved by a microwave field, and wherein an intensity of the microwave field is chosen to match an energy difference between dressed color center electronic spin eigenstates and the  13 C nuclear spins in an external magnetic field. 
     
     
         28 . The method according to  claim 27 , wherein a magnetic flux density of the external magnetic field is smaller than 3 T. 
     
     
         29 . The method according to  claim 21 , wherein the color centers include nitrogen vacancy (NV) centers. 
     
     
         30 . The method according to  claim 21 , wherein the optical polarizing step and the transferring step are repeated cyclically. 
     
     
         31 . A system for hyperpolarizing a sample, comprising:
 a diamond or a plurality of diamond particles having color centers, wherein a sample is placed near or in contact with the diamond or the plurality of diamond particles;   a magnet configured to generate a magnetic field about the diamond or the plurality of diamond particles having color centers;   a laser configured to optically polarize the color centers; and   a microwave source configured to facilitate transfer of the polarization from the color centers to  13 C nuclear spins in the diamond or the plurality of diamond particles at a temperature higher than or equal to 77K and lower than about 298K,   wherein the polarization is propagated from the  13 C nuclear spins to  13 C nuclear spins in the sample at the temperature.   
     
     
         32 . The system according to  claim 31 , wherein the magnet further includes at least one of a permanent magnet or an electromagnet. 
     
     
         33 . The system according to  claim 31 , wherein the sample is placed in contact with the diamond or the plurality of diamond particles after the  13 C nuclear spins are already hyperpolarized. 
     
     
         34 . The system according to  claim 31 , wherein the sample is placed in contact with the diamond or plurality of diamond particles before the polarization of the  13 C nuclear spins. 
     
     
         35 . The system according to  claim 31 , wherein the microwave source is configured to apply at least one of a microwave field or a radio frequency (RF) field. 
     
     
         36 . The system according to  claim 35 , wherein at least one of the microwave field or the RF field applied is pulsed. 
     
     
         37 . The system according to  claim 31 , wherein the polarization from the color centers is transferred to the  13 C nuclear spins in the diamond or the plurality of diamond particles via a long-range interaction while fulfilling the Harman-Hahn condition. 
     
     
         38 . The system according to  claim 37 , wherein the Hartmann-Hahn condition is achieved by a microwave field, and wherein an intensity of the microwave field is chosen to match an energy difference between dressed color center electronic spin eigenstates and the  13 C nuclear spins in an external magnetic field. 
     
     
         39 . The system according to  claim 38 , wherein a magnetic flux density of the external magnetic field is smaller than 3 T. 
     
     
         40 . The system according to  claim 31 , wherein the color centers include nitrogen vacancy (NV) centers.