Parallel dipole line trap with variable gap and tunable trap potential

Patent metadata

Field	Value
Publication number	US-9978493-B2
Application number	US-201615131566-A
Country	US
Kind code	B2
Filing date	Apr 18, 2016
Priority date	Apr 18, 2016
Publication date	May 22, 2018
Grant date	May 22, 2018

Abstract

Techniques for tuning magnetic potential using a variable gap in a parallel dipole line (PDL) trap are provided. In one aspect, a PDL trap is provided. The PDL trap includes: a pair of dipole line magnets separated from one another by a variable gap g; and a diamagnetic object levitating above the dipole line magnets. The dipole line magnets can be separated from one another by at least one spacer, or a variable gap fixture can be used in which the dipole line magnets are affixed to separate mounts for varying the gap g between the dipole line magnets. A bigger trap or track can be built with multiple segments of PDL trap. A method of operating a PDL trap is also provided.

First claim

What is claimed is:

1. A parallel dipole line (PDL) trap, comprising:
a pair of dipole line magnets separated from one another by a variable gap g; and
a diamagnetic object levitating above the dipole line magnets, wherein the gap g is less than a critical gap g C beyond which the diamagnetic object is no longer levitated, and wherein the gap g determines a height by which the diamagnetic object levitates above the dipole line magnets,
wherein the PDL trap further comprises a variable gap fixture in which the dipole line magnets are affixed to separate mounts in a manner whereby the mounts partially surround the dipole line magnets so as to leave the gap g between the dipole line magnets unobstructed by the mounts, the variable gap fixture further comprising:
a first screw at a bottom of the variable gap fixture below the dipole line magnets that connects the mounts to one another, wherein the first screw adjusts a positioning of the mounts relative to one another to vary the gap g between the dipole line magnets; and
a second screw at the bottom of the variable gap fixture, wherein the second screw is oriented orthogonal to the first screw such that second screw locks the positioning of the mounts adjusted by the first screw.

2. The PDL trap of claim 1 , wherein the diamagnetic object comprises a diamagnetic rod.

3. The PDL trap of claim 2 , wherein the diamagnetic rod comprises a graphite rod.

4. The PDL trap of claim 1 , wherein the diamagnetic object is an elongated diamagnetic object having an ornamental shape.

5. The PDL trap of claim 1 , wherein the dipole line magnets are separated from one another by at least one spacer.

6. The PDL trap of claim 1 , further comprising:
a light source above the dipole line magnets; and
photodetectors beneath the dipole line magnets, wherein the photodetectors are in line of site of the light source via the gap g separating the dipole line magnets, and wherein the photodetectors comprise:
at least one first photodetector proximal to a first side of the dipole line magnets; and
at least one second photodetector proximal to a second side of the dipole line magnets, wherein the diamagnetic object when at the first side of the PDL trap blocks light from the light source from reaching the at least one first photodetector, and wherein the diamagnetic object when at the second side of the PDL trap blocks the light from the light source from reaching the at least one second photodetector.

7. The PDL trap of claim 6 , wherein the light source is selected from the group consisting of: an incandescent light bulb, a light emitting diode, a laser, and combination thereof, and wherein the photodetector is selected from the group consisting of: a semiconductor photodetector, a light-dependent-resistor, and combinations thereof.

8. The PDL trap of claim 1 , wherein a longitudinal axis of the dipole line magnets is straight.

9. The PDL trap of claim 1 , wherein the dipole line magnets are curved.

10. A system, comprising:
multiple PDL traps combined to form a dipole line track system,
wherein each of the PDL traps comprises a pair of dipole line magnets separated from one another by a variable gap g, and a diamagnetic object levitating above the dipole line magnets, wherein the gap g is less than a critical gap g C beyond which the diamagnetic object is no longer levitated, and wherein the gap g determines a height by which the diamagnetic object levitates above the dipole line magnets,
wherein the dipole line magnets of at least one of the PDL traps are curved, and
wherein each of the PDL traps further comprises a variable gap fixture in which the dipole line magnets are affixed to separate mounts in a manner whereby the mounts partially surround the dipole line magnets so as to leave the gap g between the dipole line magnets unobstructed by the mounts, the variable gap fixture further comprising:
a first screw at a bottom of the variable gap fixture below the dipole line magnets that connects the mounts to one another, wherein the first screw adjusts a positioning of the mounts relative to one another to vary the gap g between the dipole line magnets; and
a second screw at the bottom of the variable gap fixture, wherein the second screw is oriented orthogonal to the first screw such that second screw locks the positioning of the mounts adjusted by the first screw.

11. A method of operating a PDL trap, comprising the steps of:
providing the PDL trap having a pair of dipole line magnets, and a diamagnetic object levitating above the dipole line magnets;
opening a gap g between the dipole line magnets, wherein the gap g is less than a critical gap g C beyond which the diamagnetic object is no longer levitated, and wherein the gap g determines a height by which the diamagnetic object levitates above the dipole line magnets,
wherein the PDL trap further comprises a variable gap fixture in which the dipole line magnets are affixed to separate mounts in a manner whereby the mounts partially surround the dipole line magnets so as to leave the gap g between the dipole line magnets unobstructed by the mounts, the variable gap fixture further comprising:
a first screw at a bottom of the variable gap fixture below the dipole line magnets that connects the mounts to one another, wherein the first screw adjusts a positioning of the mounts relative to one another to vary the gap g between the dipole line magnets; and
a second screw at the bottom of the variable gap fixture, wherein the second screw is oriented orthogonal to the first screw such that second screw locks the positioning of the mounts adjusted by the first screw, the method further comprising the steps of:
adjusting a positioning of the mounts relative to one another using the first screw to open the gap g between the dipole line magnets; and
locking the gap g in position using the second screw.

12. The method of claim 11 , further comprising the step of:
inserting at least one spacer between the dipole line magnets to open the gap g between the dipole line magnets.

13. The method of claim 11 , further comprising the step of:
turning the first screw to adjust the positioning of the mounts relative to one another.

14. The method of claim 11 , further comprising the step of:
varying the gap g to change the height by which the diamagnetic object levitates above the dipole line magnets.

15. The method of claim 11 , wherein the diamagnetic object comprises a diamagnetic rod.

16. The method of claim 11 , wherein the diamagnetic object is an elongated diamagnetic object having an ornamental shape.

17. The method of claim 11 , wherein the PDL trap further comprises a light source above the dipole line magnets, and photodetectors beneath the dipole line magnets, wherein the photodetectors are in line of sight of the light source via the gap g separating the dipole line magnets, and wherein the photodetectors comprise at least one first photodetector proximal to a first side of the dipole line magnets, and at least one second photodetector proximal to a second side of the dipole line magnets, the method further comprising the step of:
determining a position of the diamagnetic object in the PDL trap using the light source and the photodetectors, wherein the diamagnetic object when at the first side of the PDL trap blocks light from the light source from reaching the at least one first photodetector, and wherein the diamagnetic object when at the second side of the PDL trap blocks the light from the light source from reaching the at least one second photodetector.

Assignees

• IBM

Inventors

• Gunawan Oki

Classifications

• H01F7/0236 Primary

  Magnetic suspension or levitation (for vehicles B60L13/04; magnetic bearings F16C39/063) · CPC title

• H01J49/00

  Particle spectrometers or separator tubes · CPC title

• H02N15/00

  Holding or levitation devices using magnetic attraction or repulsion, not otherwise provided for (electric or magnetic devices for holding work on machine tools B23Q3/15 {; monorail vehicle propulsion or suspension B60L13/00}; sliding or levitation devices for railway systems B61B13/08; material handling devices associated with conveyors incorporating devices with electrostatic or magnetic grippers B65G47/92; separating thin or filamentary articles from piles using magnetic force B65H3/16; delivering thin or filamentary articles from magnetic holders by air blast or suction B65H29/24; bearings using magnetic or electric supporting means F16C32/04; relieving bearing loads using magnetic means F16C39/06; magnets H01F7/00; dynamo-electric clutches or brakes H02K49/00 {; electric furnaces with simultaneous levitation and heating H05B6/32}) · CPC title