【正文】 the IV curve at T=13 K Candidate schematic image of single molecular orientation switching of TbC82 ? NDC here is interpreted in terms of a switching of the TbC82 molecular orientation caused by the interaction between its electric dipole moment and an external electric field. ? At higher temperature, the electric dipole moment of the TbC82 molecule tend to be oriented at random by thermal energy, so no NDR appears. Y. F. Li et al., APL 90, 073106 (2022) IDSVDS curve VG=?20 V at RT IDSVDS curves with VG ranging from ?30 to 30 V dI/dV curve for empty DWNTs ? peaktovalley current ratio is about 1300 ? Gate voltage dependence characteristics of IDSVDS curves indicates that a threshold voltage Vth for the appearance of current peak is greatly affected by gate voltage. ?NDR characteristic is symmetrical C60filled DWNT NDR effect in DyC82 molecules Total charge density at Fermi level and total current distribution (C60)2 (LiC60)2 Tomoya Ono et al., PRL 98, 026804 (2022) Conduction Energy band structures of chains with infinite length C60 Li LiC60 nonmetallic metallic nonmetallic As electrons are inserted into the fullerenes from inserting atoms, the unoccupied state around the junction is filled and the conductivity can be significantly improved. C60 (C60)2 (LiC60)2 tu1,x tu1,y tu1,z Channel transmissions at the Fermi level Brian Larade et al., PRB 64, 195402 (2022) The IV curves Al(100)C80Al(100) system Al(100)Sc3NC80Al(100) device of two orientation ? The current through the Sc3NC80 device is double that through a bare C80 device. ? The presence of the Sc3N metal plex and its associated charge transfer to the C80 cage aligns the level with the electrodes’ Fermi level. NEGFDFT method Internal current distribution of the molecular bridge for the electron energy which is just below the LUMO of C60 ? The magnitude of the quantum loop current is much larger than that of the sourcedrain current ISD. ? The direction of the magic moment associated with this loop current is reversed if the electron energy is swept across the resonant levels. ? Under certain conditions, the induced magic moment is restricted to a single particular plane regardless of the drain site for any fixed source position. ? These features could be applied, in principle, to quantum mechanical devices by using the quantum coupling to magic atoms. Shousuke Nakanishi et al., PRL 87, 126801 (2022) Peapod structure D. E. Luzzi et al., Nature 396, 323 (1998) HRTEM image of SWNT containing C60 The dI/dV spectra (red and blue lines) at two locations. The dashed purple line is for spectra of SWNT without C60. Structure and STM imaging of a peapod. (b) + 700pA。A) architecture Gatecontrolled rectifying behavior Gatecontrolled rectifying IDSVDS characteristics after electrical breakdown. Inset: almost linear IDSVDS curve for pristine device. ? C70SWNT works ? Gatecontrolled rectification behavior at room temperature in air ? The current rectification results from highly asymmetric Schottky barriers between semiconducting peapods and the S/D electrodes Yunyi Fu et al., JPCB 110, 9923 (2022) Magoresistance NiC60Ni system (experiment) (Left) Artist39。 團(tuán)簇電離后可通過四極譜儀、靜電或磁譜儀，以及飛行時(shí)間質(zhì)譜儀 (TOF)探測(cè)。 5nm Ni:點(diǎn)陣參數(shù)縮小 % (d).磁化率 納米粒子的磁性與它所含的總電子數(shù)的奇偶性密切相關(guān)。 (表體比大） (2).磁學(xué)性質(zhì) (a).超順磁性 為粒子磁距，磁化強(qiáng)度：時(shí)：，對(duì)于超順磁性：矯頑力???TkHMTkHHBPBc3102????起源：在小尺寸下，當(dāng)各向異性能減少到與熱運(yùn)動(dòng)能可想比擬時(shí)，磁化方向就不再固定在一個(gè)易磁化方向，易磁化方向作無規(guī)律的變化，結(jié)果導(dǎo)致超順磁性的出現(xiàn)。 FeNi薄膜中疇壁運(yùn)動(dòng)速度在低于某一臨界溫度時(shí)基本上與溫度無關(guān)。 L,?的環(huán)的電流總電子數(shù)為 iNNiNNN NIINI ii :)(,)(1)(1??? ???????1 00 /),2s i n ()c os (12)(lFFN LNklLlklII ?????? ＝???????偶數(shù)當(dāng)奇數(shù)當(dāng),...,6,4,2,1,...,5,3,1,0)c os ()c os (llNlLlkNNF ?對(duì)不同總電子數(shù)的系綜的平均 .. .)()()( )4()2( ??? NNNNNN III ???(2).變型巨正則系綜 (Modified grand canonical ensemble) 不同環(huán)的化學(xué)勢(shì)可以不同，其他參數(shù)均相同。的偶函數(shù)，以是?????????)()()(242)(02022222IEnmLmkEnnn?????對(duì)一維環(huán)且沒有無序， T=0K時(shí)總電流的大小與符號(hào)由最高占據(jù)能級(jí)的電流決定。 電子自由程接近或超過樣品尺寸，關(guān)聯(lián)效應(yīng)可遍及整個(gè)樣品。 (4)移動(dòng)一個(gè)雜質(zhì)所引起的電導(dǎo)漲落 電子量子干涉－依賴于不同的費(fèi)曼路徑 → 雜質(zhì)位形對(duì)電導(dǎo) 漲落有較大影響。39。39。與樣品的材料、尺寸、無序程度無關(guān)，與樣品的形狀和空間維度只有微弱的關(guān)系，只要求樣品具有介觀尺度，并處于金屬區(qū)：即 ?? ? ??????? LLlF普適電導(dǎo)漲落的存在反映了介觀體系和宏觀體系本質(zhì)上的差別 REPRODUCIBILITY OF THE CONDUCTANCE FLUCTUATIONS MEASURED IN A GOLD RING S. Washburn and R. A. Webb Adv. Phys. 35, 375 (1986) (2)物理解釋 從樣品一邊到另一邊的透射幾率幅是許多通過樣品的費(fèi)曼路徑相應(yīng)的幾率幅之和。21)()]()([)(39。39。 LandauerButtiker公式 導(dǎo)線寬度很窄，各子能帶之間的能差很大，最低子能帶可被電子占據(jù)，成為唯一的容許通道。)()(242)(, . . .2,1,0),(2~)()(:)0()()()(2:000????????????????????????????nnnnikxixLxiEnmLmkEnnLkexmmehcedxddxdeLxExdxdmA???????????????????????????上述問題與周期為 L的一維能帶問題相似： 一一對(duì)應(yīng)kL?02???)(?nE20?? 20?雜質(zhì)－ Peierls 理想環(huán) 非理想環(huán) 實(shí)驗(yàn)： 1983年， Au的平均直徑為 245nm,環(huán)寬 30nm AAS效應(yīng)：除了觀察到 AB效應(yīng)，還觀察到周期為 的效應(yīng) 振幅只有 AB效應(yīng)的 4% 緣由：弱局域化效應(yīng) 周期相位差提供相變改變矢勢(shì)沿逆時(shí)針方向路徑提供相變改變矢勢(shì)沿順時(shí)針方向路徑ehc22 ?????ehc22．介觀體系的電導(dǎo) (1)Kubo（久保公式） 線性響應(yīng)理論：非局域響應(yīng)關(guān)聯(lián)函數(shù) ),(21 xx?自由電子體系無外電場(chǎng):, 0^0 HH ??? ??? ??? ? ?? )()()()(39。39。的偶函數(shù)，以是能量本征值為：令方程的解：件發(fā)生改變時(shí)，磁場(chǎng)存在使邊界條為整數(shù)當(dāng)磁通量子。 A B C F 量子磁通ehceeAB F ldAildAcie ???? ??? 0202211 ,: 101 ???? ???? 202022:ldAieAC F ???21 ??? ＋＝點(diǎn)干涉F)](2c os [2|||||| 21002012022012 ?? ?????? ldAldA??????02022 ??? ??若? ???? ???? ldA,2c os||2||2||020202 ????干涉強(qiáng)度依賴于兩條路徑封閉的磁通總量 ，并以周期 振蕩。),(39。和作規(guī)范變換：，當(dāng)????????????????