[1] Wolf S A, and Treger D M 2001 Science 294
1488

[2] L\"u R and Liu Z R 2002 cond-mat/0210350

[3] Goldhaber-Gordon D, Shtrikman H, Mahalu D, Meirav U and
Kastner M A 1998 Nature 391 156

[4] Kouwenhoven L P and Glazman L 2001 Phys. World
14 33

[5] Aguado R et al 2000 Phys. Rev. Lett. 85 1946

[6] Jeong H et al 2001 Science 293 2221

Van der Wiel W G et al 2002 Preprint cond-mat/0205350

[7] Yoffe A D 2001 Adv. Phys. 50 1

Dai Z H et al 2002 Chin. Phys. Lett. 19 117

[8] Izumida W and Sakai O 2000 Phys. Rev. B 62
10260

[9] Yi L and Wang S J 2002 Chin. Phys. Lett. 19
1333

Xiao M W et al 2002 Chin. Phys. Lett. 19 1961

[10] Jones B A, Varma C M and Wilkins J W 1998 Phys. Rev.
Lett. 61 125

[11] Zhang P, Xue Q K, Wang Y P and Xie X C 2002 Phys.
Rev. Lett. 89 286803

[12] Meir Y, Wingreen N S and Lee P A 1993 Phys. Rev.
Lett. 70 2601

[13] Wu S Q and Wang S J 2003 Chin. Phys. Lett.
20 1574

[14] Swirkowicz R, Barnas J, and Wilczynski M 2003
Phys. Rev. B 68 195318

[15] Bj\"orn K and J\"urgen K 2002 Phys. Rev. B 65
245301