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Cyclotron resonance

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It is notable that the cyclotron frequency is independent of the radius and velocity and therefore independent of the particle's kinetic energy; all particles with the same charge-to-mass ratio rotate around magnetic field lines with the same frequency. This is only true in the non-relativistic
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The cyclotron frequency is also useful in non-uniform magnetic fields, in which (assuming slow variation of magnitude of the magnetic field) the movement is approximately helical - in the direction parallel to the magnetic field, the motion is uniform, whereas in the plane perpendicular to the
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For some materials, the motion of electrons follows loops that depend on the applied magnetic field, but not exactly the same way. For these materials, we define a cyclotron effective mass,
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Since the motion in an orthogonal and constant magnetic field is always circular, the cyclotron frequency is given by equality of
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magnetic field the movement is, as previously circular. The sum of these two motions gives a trajectory in the shape of a
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When the charged particle begins to approach relativistic speeds, the centripetal force should be multiplied by the
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that utilizes an oscillating electric field tuned to this resonance to add kinetic energy to charged particles.
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describes the interaction of external forces with charged particles experiencing a
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Note that converting this expression to SI units introduces a factor of the
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Effective mass (solid-state physics) § Cyclotron effective mass
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moving perpendicular to the direction of a uniform magnetic field
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Physics by M. Alonso & E. Finn, Addison Wesley 1996.
53:, thus moving on a circular path. It is named after the 582:{\displaystyle \omega ={\frac {v}{r}}={\frac {qB}{mc}}} 444:
limit, and underpins the principle of operation of the
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Diagram of a cyclotron orbit of a particle with speed
760: 730: 665: 625: 599: 539: 522:. In some cases, the cyclotron frequency is given in 472: 381: 319: 235: 162: 112: 791: 743: 694: 637: 611: 581: 501: 431: 356: 272: 201:{\displaystyle \omega _{\rm {c}}={\frac {qB}{mc}}} 200: 145: 146:{\displaystyle \omega _{\rm {c}}={\frac {qB}{m}}} 932: 869:Calculate Cyclotron frequency with Wolfram Alpha 593:For materials with little or no magnetism (i.e. 64: 855:Ashcroft and Mermin. Solid State Physics. pp12 502:{\displaystyle \omega ={\frac {qB}{\gamma m}}} 915: 792:{\displaystyle \omega ={\frac {qB}{m^{*}}}} 922: 908: 695:{\displaystyle \omega ={\frac {qH}{mc}}} 29: 273:{\displaystyle {\frac {mv^{2}}{r}}=qBv} 14: 946:Electric and magnetic fields in matter 933: 827: 530:, the speed of light, which leads to: 85:(constant magnitude and direction). 874: 645:, so we can use the easily measured 372:(being the cyclotron frequency) as: 844:Introduction to Solid State Physics 24: 169: 119: 25: 972: 862: 713: 513: 878: 295:, and the circular path radius 849: 836: 13: 1: 820: 612:{\displaystyle \mu \approx 1} 214: 65:Cyclotron resonance frequency 894:. You can help Knowledge by 815:Electron cyclotron resonance 7: 803: 27:Motion of charged particles 10: 977: 873: 717: 638:{\displaystyle H\approx B} 961:Accelerator physics stubs 647:magnetic field intensity 98: 93: 941:Condensed matter physics 810:Ion cyclotron resonance 283:with the particle mass 890:-related article is a 846:, 8th edition. pp. 153 793: 745: 696: 639: 613: 583: 503: 433: 358: 274: 202: 147: 77:is the frequency of a 43: 956:Scientific techniques 794: 746: 744:{\displaystyle m^{*}} 697: 640: 614: 584: 504: 434: 359: 275: 203: 148: 33: 758: 728: 663: 623: 597: 537: 470: 379: 370:rotational frequency 317: 233: 160: 110: 89:Cyclotron frequency 59:particle accelerator 951:Accelerator physics 888:accelerator physics 708:vacuum permeability 90: 71:cyclotron frequency 47:Cyclotron resonance 18:Cyclotron frequency 789: 741: 692: 635: 609: 579: 499: 429: 354: 270: 198: 143: 88: 44: 903: 902: 842:Kittel, Charles. 787: 690: 577: 554: 518:The above is for 497: 427: 401: 352: 334: 256: 221:centripetal force 212: 211: 196: 141: 16:(Redirected from 968: 924: 917: 910: 882: 875: 856: 853: 847: 840: 834: 831: 798: 796: 795: 790: 788: 786: 785: 776: 768: 750: 748: 747: 742: 740: 739: 701: 699: 698: 693: 691: 689: 681: 673: 644: 642: 641: 636: 618: 616: 615: 610: 588: 586: 585: 580: 578: 576: 568: 560: 555: 547: 508: 506: 505: 500: 498: 496: 488: 480: 438: 436: 435: 430: 428: 426: 415: 407: 402: 400: 389: 363: 361: 360: 355: 353: 348: 340: 335: 327: 279: 277: 276: 271: 257: 252: 251: 250: 237: 207: 205: 204: 199: 197: 195: 187: 179: 174: 173: 172: 152: 150: 149: 144: 142: 137: 129: 124: 123: 122: 91: 87: 79:charged particle 21: 976: 975: 971: 970: 969: 967: 966: 965: 931: 930: 929: 928: 865: 860: 859: 854: 850: 841: 837: 832: 828: 823: 806: 781: 777: 769: 767: 759: 756: 755: 735: 731: 729: 726: 725: 722: 716: 682: 674: 672: 664: 661: 660: 624: 621: 620: 598: 595: 594: 569: 561: 559: 546: 538: 535: 534: 516: 489: 481: 479: 471: 468: 467: 416: 408: 406: 393: 388: 380: 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896:expanding it 885: 851: 838: 829: 723: 705: 653: 648: 592: 527: 517: 458: 450: 442: 367: 305: 296: 292: 288: 284: 282: 218: 156: 106: 82: 74: 70: 68: 46: 45: 39: 35: 652:instead of 368:Giving the 291:, velocity 57:, a cyclic 935:Categories 821:References 718:See also: 301:gyroradius 215:Derivation 783:∗ 762:ω 751:so that: 737:∗ 667:ω 630:≈ 604:≈ 601:μ 541:ω 491:γ 474:ω 446:cyclotron 421:π 398:π 391:ω 321:ω 310:is then: 165:ω 115:ω 100:CGS units 55:cyclotron 804:See also 520:SI units 95:SI units 886:This 454:helix 892:stub 306:The 69:The 73:or 937:: 710:. 656:: 619:) 456:. 448:. 303:. 923:e 916:t 909:v 898:. 799:. 779:m 774:B 771:q 765:= 733:m 702:. 687:c 684:m 679:H 676:q 670:= 654:B 649:H 633:B 627:H 607:1 589:. 574:c 571:m 566:B 563:q 557:= 552:r 549:v 544:= 528:c 509:. 494:m 486:B 483:q 477:= 439:, 424:m 418:2 413:B 410:q 404:= 395:2 386:= 383:f 364:. 350:m 346:B 343:q 337:= 332:r 329:v 324:= 297:r 293:v 289:q 285:m 268:v 265:B 262:q 259:= 254:r 248:2 244:v 240:m 193:c 190:m 185:B 182:q 176:= 170:c 139:m 135:B 132:q 126:= 120:c 83:B 42:. 40:B 36:v 20:)

Index

Cyclotron frequency

magnetic field
cyclotron
particle accelerator
charged particle
SI units
CGS units
centripetal force
Lorentz force
gyroradius
angular speed
rotational frequency
cyclotron
helix
Lorentz factor
SI units
Gaussian units
magnetic field intensity H
vacuum permeability
Effective mass (solid-state physics) § Cyclotron effective mass
Ion cyclotron resonance
Electron cyclotron resonance
Introduction to Solid State Physics
Calculate Cyclotron frequency with Wolfram Alpha
Stub icon
accelerator physics
stub
expanding it
v

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