As one of the most fundamental physical phenomena, the anomalous Hall effect (AHE) typically occurs in ferromagnetic materials but is not expected in the conventional superconductors. Here, we have observed a giant AHE in kagome superconductor CsV 3 Sb 5 with transition temperature (Tc) of 2.7 K. The anomalous Hall conductivity reaches up to 2.1× 10 4 Ω -1 cm -1 which is larger than those observed in most of the ferromagnetic metals. Strikingly, the emergence of AHE exactly follows the higher-temperature charge-density-wave (CDW) transition with T CDW ~ 94 K, indicating a strong correlation between the CDW state and AHE. The origin for AHE is attributed to enhanced skew scattering in CDW state and large Berry curvature arose from the kagome lattice. These discoveries make CsV 3 Sb 5 as an ideal platform to study the interplay among nontrivial band topology, CDW and unconventional superconductivity.A kagome lattice, representing a two-dimensional network with corner-sharing triangles, provides a fertile ground to study the frustrated, novel correlated and topological electronic states owing to its unusual lattice geometry[1-3]. In general, kagome lattice naturally possesses Dirac dispersion and flat bands that promote electronic correlation effect [4]. Thus, in principle, kagome lattice can exhibit a large variety of electronic instabilities. Many exotic quantum phenomena have been observed in magnetic kagome metals, including giant anomalous Hall effect (AHE) [5][6][7][8][9][10][11][12], chiral edge state [13,14], and topological surface Fermi arcs [15]. Up to now, exploring exotic properties in kagome lattice remains quite challenging, particularly for multiple electronic orders.Recently, a new family of quasi-two-dimensional kagome metals AV 3 Sb 5 (A = K, Rb, Cs) have attracted tremendous attentions [16]. These materials crystallize in the P6/mmm space group with ideal kagome nets of V atoms which are coordinated by Sb atoms. The kagome layers are sandwiched by extra antimonene layers (Sb2) and Cs layers as shown in Figure 1(a).The resistivity of AV 3 Sb 5 family exhibits anomalies at T * ranged from 80 K to 110 K, which are ascribed to the formation of charge density wave (CDW) order [16,17]. The observation of superconductivity in the stoichiometric AV 3 Sb 5 with kagome lattice [18][19][20] makes this family as

A series of new organic semiconductors for organic thin‐film transistors (OTFTs) using dithieno[3,2‐b:2′,3′‐d]thiophene as the core are synthesized. Their electronic and optical properties are investigated using scanning electron microscopy (SEM), X‐ray diffraction (XRD), UV‐vis and photoluminescence spectroscopies, thermal gravimetric analysis (TGA), and differential scanning calorimetry (DSC). The compounds exhibit an excellent field‐effect performance with a high mobility of 0.42 cm2 V–1 s–1 and an on/off ratio of 5 × 106. XRD patterns reveal these films, grown by vacuum deposition, to be highly crystalline, and SEM reveals well‐interconnected, microcrystalline domains in these films at room temperature. TGA and DSC demonstrate that the phenyl‐substituted compounds possess excellent thermal stability. Furthermore, weekly shelf‐life tests (under ambient conditions) of the OTFTs based on the phenyl‐substituted compounds show that the mobility for the bis(diphenyl)‐substituted thiophene was almost unchanged for more than two months, indicating a high environmental stability.

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