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²{¦b¡A§Ú­Ì°¨¤W­±Á{¤F¤@­Ó´Æ¤âªº¶q¤l¦hÅé°ÝÃD¡C³oºØ°ÝÃD³q±`¥u¯à¥Î·LÂZ®i¶}ªº¤èªk¸Ñ¡C¹ï©ó¬Y¨Ç¨t²Î¡A¨Ò¦p¶W¾É Åé¡A·LÂZ­pºâ¨Æ¹ê¤W¥Ã»·¤£¥i¯à¾É­P¥¿½Tªºµª®×¡C¶q¤lÀNº¸²GÅé¤]¦³Ãþ¦üªº°ÝÃD¡CLaughlin ªº¹L¤H¤§³B¦b©ó¥L¥Îª«²zªº±À²zª½±µ²q¥X´X¥G¥¿½Tªº¶q¤lªi¨ç¼Æ¡C³o´N¹³ Schrieffer ¦b¤»¹s¦~¥Nª½±µ²q¥X¶W¾Éª¬ºAªºªi¨ç¼Æ¤@¼Ë¡A¬O¤@­Ó­«­nªº¦¨´N¡CLaughlin ¥Ñ³o­Óªi¨ç¼Æ¥Xµo¡A±À¥X¤F¨â­Ó­«­nªºµ²ªG (Laughlin, 1983)¡C²Ä¤@­Óµ²ªG¬O¶q¤lÀNº¸²GÅé»Ý­n¥Î¦³­­ªº¯à¶q¤~¯à³Q¿Eµo¡C³oªí¥Ü¥¦¸ò¶W¾ÉÅé¤@¼Ë¡A¦b·Å«×°÷§C®É¦]¬°¼ö¯à¤£¨¬¡A©Ò¦³¹q¤l³£¾®µ²¦b°òºA¡C©Ò¥H¾ã­Ó¨t²Î¦¨¤F¤@­Ó¥¨Æ[ªº¶q¤lºA¡C²Ä¤G­Óµ²ªG¬O¶q¤lÀNº¸²GÅ骺¿EµoºA¬O±a¦³¤À¼Æ¹q²ü (fractional charge) ªº·Ç²É¤l (quasiparticle)¡C³o¸Ìªº¤À¼Æ¹q²ü¥¿¬O¶q¤lÀNº¸¹qªý·|¦³¤À¼Æ¥­¥xªº­ì¦]¡C

ÁöµM Laughlin, Stormer, ¸òTsuiµ¥¤T¤H¬O¦]¬°¦b¤À¼Æ¶q¤lÀNº¸®ÄÀ³¤Wªº¬ã¨sÀò¼ú¡C¦³ ½ìªº¬O¿Õ¨©º¸¼úªºµ¹¼ú­ì¦]¸Ì¨Ã¨S¦³´£¨ì¡§¤À¼Æ¶q¤lÀNº¸®ÄÀ³¡¨³o­Ó¦Wµü¡A¦Ó¬O±j½Õ¥L­Ìµo ²{¤F¡§¤@ºØ¦³¤À¼Æ¹q²ü¿EµoºAªº·s«¬¶q¤l²GÅ顨¡Cªº½T¡A¦Û±q±K¥ß®Ú¨D¥X°ò¥»¹q²üªº¤j¤p¥H¨Ó¡A³o¬O¤H ­Ì­º¦¸µo²{±a¦³¤À¼Æ¹q²üªº·Ç²É¤l¡C³o¸Ì¥²¶·±j½Õ©Ò¿×ªº·Ç²É¤l¨Ã«D°ò¥»²É¤l¡C¥¦¬O¤@¸s°ò¥»²É¤l (¦b³oùجO¹q¤l) ªº¶°¦X©Ò§Î¦¨ªº¿EµoºA¡C§Ú­Ì¨S¦³¿ìªk§â·Ç²É¤l©âÂ÷¥X¨Ó¬ã¨s¡A´N¦p¦P§Ú­Ì¨S¦³¿ìªk§âÁn­µ©âÂ÷¥XªÅ®ð³o­Ó¤¶½è¨Ó¬ã¨s¤@¼Ë¡C¦Ó¥B¡A·Ç²É¤lªº¹Ø©RÁ`¬O¦³­­ªº¡A¦]¬°¥¦­Ì¨Ã¤£¬O¶q¤l¦hÅé¨t²Îªº¥»¼xºA¡C¤£¹L°£¦¹¤§¥~¡A·Ç²É¤l©M²É¤l¤@¼Ë¥i¥H¦³¹q²ü¡N½è¶q¡N¦Û±Ûµ¥ÄÝ©Ê¡CÄY®æªº»¡¡AStormer, Tsui, ¤Î Gossard¶q¨ìªºÀNº¸¹qªýªº¤À¼Æ¥­¥x¥u¬O¶¡±µÃÒ¹ê¤F·Ç²É¤l±a¦³¤À¼Æ¹q²ü¡Cª½±µ¦Ó©ú½TªºÃÒ¹ê¬O¥h¦~¤À§O¥Ñ¥H¦â¦C©Mªk°êªº¨â­Ó¬ã¨s¤p²Õ¸g¥Ñ´ú¶q¹q¬yªº¾¸­µ°µ¥X¨Óªº (Collins, 1997)¡C

¶q¤lÀNº¸²GÅ骺ºë·L¤§³B¤ñ°_¶W¾ÉÅé©Î¶W¬yÅé¥i¿×¦³¹L¤§¦ÓµL¤£¤Î¡C¦b±Nªñ¤G¤Q¦~ªº¬ã¨sùØ¡A´X¥G¨C¹j¨â¤T¦~´N¦³¥O¤HÅå³ßªº·sµo²{¡C³o¥]¬A¦­´Á²z½×¹w´ú³oºØ·sªº·Ç²É¤l¥i¥H¤£¬O¬Á¦â¤l©Î¶O¦Ì¤l¡A¦Ó¬O¨ã¦³¤À¼Æ²Î­p (fractional statistics) ©Ê½èªº¥ô·N¤l (anyon)¡C³o©M³o­Ó¨t²Îªº¹q¤l¬O¬¡¦b¤Gºûªº¥­­±ùئ³«Ü±K¤ÁªºÃö³s¡A¤@¯ë¤TºûªºÅé¨t¨Ã¤£·|¦s¦b¨ã¦³¤À¼Æ²Î­pªº²É¤l¡C¦¹¥~¡A¬ã¨sªÌÁÙµo²{¶q¤lÀNº¸²GÅé©M¶W¬yÅé¦b§Î¦¡¤W¦³«Ü¦hÃþ¦üªºÃö«Y¡A©M©Ý¾ë¾Çùتº³¯¤ó¯Å (Chern Class) ¤]¦³¤@¨ÇÀu¶®ªºÃöÁp (¤E¹s¦~¥H«eªº¬ã¨s½Ð¨£Prange and Girvin, 1990)¡C

¦b¤E¹s¦~¥Nªì¡Aª«²z¾Ç®a´¶¹M»{¬°Ãö©óÀNº¸²GÅé¸Óµo²{ªº¥þ³Qµo²{¤F¡C«á¨Ó«o¤@¦A¦³¥X¤H·N ®Æªº¶i®i¡C¥]¬Aª«²z¾Ç®aªø¤[¥H¨Ó¦b¨ä¥¦¾®ºA¨t²Î¹M´M¤£µÛªº Luttinger liquid¡A«o¦bÀNº¸²GÅé¸Ì§ä¨ì¡C ¦¹¥~¡AÁÙµo²{composite fermion ¤Î skyrmion µ¥ªº¨ä¥L·s«¬·Ç²É¤l,¥H¤Îµo²{¹q²ü¡X±Û´õªº¹ï°¸©Ê½è (charge-vortex duali ty) µ¥ (¸ûªñ´X¦~ªºµo®i½Ð¨£ Das Sarma and Pinczuk, 1996)¡CÀNº¸¹qªý¥­¥x¥Ñ©ó¥i¥H³Qºë½Tªº´ú¶q¡A´X¦~«e¤w³Q±Ä¥Î¬°¹qªýªº·s¼Ð·Ç¡C¶q¤lÀNº¸²GÅ饻¨­ÁöµM¤´¨S¦³¹ê»Úªº¥Î³~¡A¦ý¬O³o¤è­±ªº¬ã¨sª½±µªº¨ë¿E¤F¥b¾ÉÅ餶­±¤Î¤¤Æ[ª«²z (mesoscopic physics) ªº¶i®i¡C«áªÌ²o¯A¨ì¨ì¶q¤l½u (quantum wire) ¶q¤lÂI (quantum dot) µ¥©`¦Ì¤Ø«× (nano-scale) ªº¤H³yµ²ºc¡A¬O»s³y¤U¤@¥@¬öªº­pºâ¾÷©Ò¥²¶·­±¹ïªº½ÒÃD¡C¶q¤lÀNº¸®ÄÀ³ªºµo²{¡A¤w¸g¬°§Ú­Ì±a¨Ó¤F¤@­ÓÂ×´IªºÄ_ÂáC¤µ¦~ªºÀò¼ú¡A¥i¿×¹ê¦Ü¦WÂk¡C

°Ñ¦Ò¤åÄm

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S. Das Sarma and A. Pinczuk eds., Perspectives in Quantum Hall Effects : Novel Quantum Liquids in Low-Dimensional Semiconductor Structures, John Wiley and Sons (1996).

R.B. Laughlin, Quantized Hall conductivity in two dimensions, Phys. Rev. B 23, 5632 (1981).

R.B. Laughlin, Anomalous quantum Hall effect ¡V an incompressible quantum fluid with fractionally charged excitations, Phys. Rev. Lett. 50, 1395 (1983).

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D.C. Tsui, H.L. Stormer, and A.C. Gossard, Two-dimensional magnetotransport in the extreme quantum limit, Phys. Rev. Lett. 48, 1559 (1982).

K. von Klitzing, G. Gorda, and M. Pepper, New method for high-accuracy determination of the fine-structure constant based on quantized Hall resistance, Phys. Rev. Lett. 45, 494 (1980).

¶i¤@¨Bªº¾\Ū

P.W. Anderson, When the electron falls apart, Physics Today, October, p.42 (1997).

B. Davis, Splitting the electron, New Scientist, January, p.36 (1998).

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