Identification of molecules based on frequency responses using electromagnetic write-heads and magneto-resistive sensors

1. An apparatus, comprising:

an electromagnetic write-head configured to magnetically excite a molecule to be identified with an alternating magnetic field, wherein the molecule to be identified is disposed on a biosample substrate configured for use with the apparatus;

a magneto-resistive sensor configured to measure a resonant response of the magnetically excited molecule to be identified; and

a processor coupled to the magneto-resistive sensor, the processor being configured to:

compare the resonant response to a table of known resonant responses; and

identify a chemical composition of the molecule to be identified based on the comparison.

2. The apparatus of claim 1 , comprising a magnetic shield configured to prevent cross-talk between the electromagnetic write-head and the magneto-resistive sensor while the electromagnetic write-head magnetically excites the molecule to be identified.

3. The apparatus of claim 2 , comprising a position error servo (PES) read head configured to align the electromagnetic write-head and the magneto-resistive sensor with a biosample track in the biosample substrate.

4. The apparatus of claim 3 , wherein the PES read head comprises one or more of a GMR sensor, a TMR sensor, and an AMR sensor.

5. The apparatus of claim 1 , comprising a protective layer configured to electrically insulate the electromagnetic write-head from the molecule to be identified.

6. The apparatus of claim 5 , the protective layer comprising diamond-like carbon (DLC).

7. The apparatus of claim 1 , comprising an outer layer configured to protect the electromagnetic write-head from corrosion.

8. The apparatus of claim 7 , the outer layer comprising one or more of gold and platinum.

9. The apparatus of claim 1 , the electromagnetic write-head comprising a thin-film write-head.

10. The apparatus of claim 1 , comprising a protective layer configured to electrically insulate the magneto-resistive sensor from the molecule to be identified.

11. The apparatus of claim 10 , the protective layer comprising diamond-like carbon (DLC).

12. The apparatus of claim 1 , comprising an outer layer configured to protect the magneto-resistive sensor from corrosion.

13. The apparatus of claim 12 , the outer layer comprising one or more of gold and platinum.

14. The apparatus of claim 1 , the processor being configured to identify the chemical composition in response to determining, based on the comparison, a correlation between the measured resonant response of the magnetically excited molecule to be identified and an ideal resonant response for the chemical composition exceeds a predetermined correlation threshold.

15. The apparatus of claim 1 , the resonant response table comprising a matched filter.

16. The apparatus of claim 1 , comprising a magnet configured to facilitate the measurement of the resonant response by exposing the molecule to be identified to a DC magnetic field while the molecule to be identified is being magnetically excited by the alternating magnetic field.

17. The apparatus of claim 1 , the biosample substrate comprising a plurality of biosample tracks.

18. The apparatus of claim 1 , comprising:

a plurality of the electromagnetic write-heads; and

a plurality of the magneto-resistive sensors; and

wherein the electromagnetic write-heads and the magneto-resistive sensors are arranged in a plurality of head/sensor pairs.

19. The apparatus of claim 1 , comprising an amplifier configured to amplify the resonant response of the magnetically excited molecule to be identified.

20. The apparatus of claim 1 , wherein the biosample substrate comprises one or more of a Peltier substrate and a magnetic tape medium.