Knowledge

Helicon (physics)

Source đź“ť

149:(ICP) is the presence of a magnetic field directed along the axis of the antenna. The presence of this magnetic field creates a helicon mode of operation with higher ionization efficiency and greater electron density than a typical ICP. The Australian National University, in Canberra, Australia, is currently researching applications for this technology. A commercially developed magnetoplasmadynamic engine called 114:
The practical significance of the surface mode, and its ultra-high current density, was not recognized in the original papers, but came to prominence a few years later when Boswell discovered the superior plasma generating ability of helicons – achieving plasma charge densities 10 times higher than
402:
Longmier, B. W., Squire, J. P., Cassady, L. D., Ballenger, M. G. Carter, M. D., Olsen, C., Ilin, A. V., Glover, T. W., McCaskill, G. E., Chang Diaz, F. R., Bering III, E. A., and Del Valle, J. (September 2011) “VASIMR® VX-200 Performance Measurements and Helicon Throttle Tables Using Argon and
110:
loss in such surface regions tends to a non-zero limit. The surface mode is especially prevalent in cylindrical samples parallel to the magnetic field, a configuration for which an exact solution has been found for the equations, and which figures importantly in subsequent experiments.
375:
Marini, C., Agnello, R., Duval, B. P., Furno, I., Howling, A. A., Jacquier, R., Karpushov, A. N., Plyushchev, P., Verhaegh, K., Guittienne, Ph., Fantz, U., WĂĽnderlich, D., BĂ©chu, S., and Simonin, A. (January 2017) "Spectroscopic characterization of
310:
Klozenberg, J. P., McNamara, B., and Thonemann, P. C. (March 1965) "The dispersion and attenuation of helicon waves in a uniform cylindrical plasma". Journal of Fluid Mechanics 21 (3): 545–563. DOI:10.1017/S0022112065000320.
300:
Goodman, J. M. (15 July 1968) "Helicon waves, surface-mode loss, and the accurate determination of the Hall coefficients of Aluminum, Indium, Sodium, and Potassium". Physical Review 171 (1): 641–658. DOI:
93:
in a metal: the electric or magnetic fields are quickly reflected upon trying to enter the metal. (Hence the shine of metals.) However, skin depth depends on an inverse proportionality to the square root of
332:
Boswell, R. W. (October 1984) "Very efficient plasma generation by whistler waves near the lower hybrid frequency". Plasma Physics and Controlled Fusion 26 (10): 1147–1162. DOI:10.1088/0741-3335/26/10/001.
393:
Charles, C., Boswell, R. W., and Lieberman, M. A. (December 2006) "Xenon ion beam characterization in a helicon double layer thruster." Applied Physics Letters 89:261503 (3 pgs) DOI: 10.1063/1.2426881.
105:
term) is that at places where the sample surface runs parallel to the magnetic field, one of the modes contains electric currents that “go to infinity" in the limit of perfect conductivity; so that the
220:
Bowers, R., Legéndy, C. R., and Rose, F. E. (November 1961) "Oscillatory galvanomagnetic effect in metallic Sodium". Physical Review Letters 7 (9): 339–341. DOI: 10.1103/PhysRevLett.7.339.
270:
Aigrain, P. (1961) Proceedings of the International Conference on Semiconductor Physics (Publishing House of the Czechoslovak Academy of Science, Prague, 1961) p. 224.
291:
Goodman, J. M. and Legéndy, C. R. (May 1964) "Joule loss in a 'perfect' conductor in a magnetic field". Cornell University Materials Science Center Report No. 201.
171: 131: 350:
Chen, F. F. (December 1996) "Helicon plasma sources" in: High Density Plasma Sources: Design, Physics and Performance, Oleg A. Popov (ed) (Elsevier-Noyes) print
425:
Poulsen, R. G. (1977) "Plasma etching in integrated circuit manufacture – A review" Journal of Vacuum Science and Technology 14 (1): 266 DOI: 10.1116/1.569137
341:
Boswell, R. W. and Chen F. F. (December 1997) "Helicons – the early years". IEEE Transactions on Plasma Science 25 (6): 1229–1244. DOI: 10.1109/27.650898.
118:
Since then, helicons found use in a variety of scientific and industrial applications – wherever highly efficient plasma generation was required, as in
384:
helicon plasmas generated by a resonant antenna for neutral beam applications in fusion." Nuclear Fusion 57:036024 (9pp) DOI:10.1088/1741-4326/aa53eb
319:
Boswell, R. W. (July 1970) "A study of waves in gaseous plasmas". Ph.D. Thesis, School of Physical Sciences, Flinders University of South Australia. (
363: 355: 282:
Legéndy, C. R. (September 1964) "Macroscopic theory of helicons". The Physical Review 135 (6A): A1713–A1724. DOI:10.1103/PhysRev.135.A1713.
98:. Thus a low-frequency electromagnetic wave may be able to overcome the skin depth problem, and thereby propagate throughout the material. 403:
Krypton.” 32nd International Electric Propulsion Conference, held in Wiesbaden, Germany, September 11–15, 2011 (Wiesbaden: IEPC-2011-156).
441: 66:(rather than parallel as it would be without the magnetic field); so that the propagating component of the waves is corkscrew-shaped ( 191: 101:
One property of the helicon waves (readily demonstrated by a rudimentary calculation, using only the Hall effect terms and a
166: 154: 127: 89:) acts to screen out the electromagnetic field. Indeed, normally an electromagnetic wave would experience a very thin 146: 320: 416:
selectivity and variable Si etch profiles". Applied Physics Letters 47 (10): 1095–1097 DOI: 10.1063/1.96340.
142: 134:
both make use of helicons in their plasma heating phase). Helicons are also utilized in the procedure of
123: 81:, given conditions of low temperature and high magnetic fields. Most electromagnetic waves in a normal 243: 82: 39: 412:
Boswell, R. W. and Henry D. (15 November 1985) "Pulsed high rate plasma etching with variable Si/SiO
194:". Philosophical Transactions of the Royal Society A. 246 (908): 113. DOI: 10.1098/rsta.1953.0011. 86: 359: 351: 95: 251: 63: 51: 43: 31: 247: 135: 119: 71: 55: 47: 435: 107: 54:, but they also exist in solid conductors or any other electromagnetic plasma. The 153:
also uses helicon discharge for generation of plasma in its engine. Potentially,
17: 141:
A helicon discharge is an excitation of plasma by helicon waves induced through
102: 90: 59: 321:
http://people.physics.anu.edu.au/~rwb112/hr/index.htm#Boswell_Thesis_directory
85:
are not able to do this, since the high conductivity of metals (due to their
256: 231: 150: 205: 115:
had been achieved with earlier methods, without a magnetic field.
78: 67: 157:
plasma-based rockets are suitable for interplanetary travel.
77:
Helicons have the special ability to propagate through pure
27:
Low-frequency EM wave created in plasmas by a magnetic field
145:. The difference between a helicon plasma source and an 138:, used in the manufacture of computer microcircuits. 278: 276: 50:. The first helicons observed were atmospheric 210:(Ph.D thesis). Australian National University. 172:Variable Specific Impulse Magnetoplasma Rocket 132:Variable Specific Impulse Magnetoplasma Rocket 8: 192:An investigation of whistling atmospherics 255: 70:) – hence the term “helicon,” coined by 183: 62:, and is nearly at right angles to the 207:Helicon Waves in High Density Plasmas 7: 25: 58:in the waves is dominated by the 190:Storey, L. R. O. (9 July 1953) " 1: 167:Helicon double-layer thruster 155:helicon double-layer thruster 128:helicon double-layer thruster 204:Darryn A. Schneider (1998). 236:American Journal of Physics 458: 147:inductively coupled plasma 42:that can exist in bounded 442:Electromagnetic radiation 232:"Helicon Waves in Solids" 301:10.1103/PhysRev.171.641. 143:radio frequency heating 230:B.W. Maxfield (1969). 46:in the presence of a 40:electromagnetic wave 248:1969AmJPh..37..241M 38:is a low-frequency 364:978-0-8155-1789-4 356:978-0-8155-1377-3 257:10.1119/1.1975500 96:angular frequency 18:Helicon discharge 16:(Redirected from 449: 426: 423: 417: 410: 404: 400: 394: 391: 385: 373: 367: 348: 342: 339: 333: 330: 324: 317: 311: 308: 302: 298: 292: 289: 283: 280: 271: 268: 262: 261: 259: 227: 221: 218: 212: 211: 201: 195: 188: 124:space propulsion 122:reactors and in 64:electric current 32:electromagnetism 21: 457: 456: 452: 451: 450: 448: 447: 446: 432: 431: 430: 429: 424: 420: 415: 411: 407: 401: 397: 392: 388: 383: 379: 374: 370: 349: 345: 340: 336: 331: 327: 318: 314: 309: 305: 299: 295: 290: 286: 281: 274: 269: 265: 229: 228: 224: 219: 215: 203: 202: 198: 189: 185: 180: 163: 28: 23: 22: 15: 12: 11: 5: 455: 453: 445: 444: 434: 433: 428: 427: 418: 413: 405: 395: 386: 381: 377: 368: 343: 334: 325: 312: 303: 293: 284: 272: 263: 242:(3): 241–269. 222: 213: 196: 182: 181: 179: 176: 175: 174: 169: 162: 159: 136:plasma etching 120:nuclear fusion 87:free electrons 56:electric field 48:magnetic field 26: 24: 14: 13: 10: 9: 6: 4: 3: 2: 454: 443: 440: 439: 437: 422: 419: 409: 406: 399: 396: 390: 387: 372: 369: 365: 361: 357: 353: 347: 344: 338: 335: 329: 326: 322: 316: 313: 307: 304: 297: 294: 288: 285: 279: 277: 273: 267: 264: 258: 253: 249: 245: 241: 237: 233: 226: 223: 217: 214: 209: 208: 200: 197: 193: 187: 184: 177: 173: 170: 168: 165: 164: 160: 158: 156: 152: 148: 144: 139: 137: 133: 129: 125: 121: 116: 112: 109: 108:Joule heating 104: 99: 97: 92: 88: 84: 80: 75: 73: 69: 65: 61: 57: 53: 49: 45: 41: 37: 33: 19: 421: 408: 398: 389: 371: 346: 337: 328: 315: 306: 296: 287: 266: 239: 235: 225: 216: 206: 199: 186: 140: 117: 113: 100: 76: 35: 29: 126:(where the 103:resistivity 60:Hall effect 178:References 91:skin depth 83:conductor 52:whistlers 436:Category 358:, ebook 161:See also 130:and the 244:Bibcode 72:Aigrain 68:helical 44:plasmas 36:helicon 362:  354:  151:VASIMR 79:metals 380:and D 360:ISBN 352:ISBN 34:, a 252:doi 74:. 30:In 438:: 275:^ 250:. 240:37 238:. 234:. 414:2 382:2 378:2 376:H 366:. 323:) 260:. 254:: 246:: 20:)

Index

Helicon discharge
electromagnetism
electromagnetic wave
plasmas
magnetic field
whistlers
electric field
Hall effect
electric current
helical
Aigrain
metals
conductor
free electrons
skin depth
angular frequency
resistivity
Joule heating
nuclear fusion
space propulsion
helicon double-layer thruster
Variable Specific Impulse Magnetoplasma Rocket
plasma etching
radio frequency heating
inductively coupled plasma
VASIMR
helicon double-layer thruster
Helicon double-layer thruster
Variable Specific Impulse Magnetoplasma Rocket
An investigation of whistling atmospherics

Text is available under the Creative Commons Attribution-ShareAlike License. Additional terms may apply.

↑