Randomness is critical for many information processing applications, including numerical modeling and cryptography [1,2]. Device-independent quantum random number generation [3] (DIQRNG) based on the loophole free violation of Bell inequality [4][5][6][7] produces unpredictable genuine randomness without any device assumption and is therefore an ultimate goal in the field of quantum information science [8][9][10]. However, due to formidable technical challenges, there were very few reported experimental studies of DIQRNG [11][12][13][14], which were vulnerable to the adversaries. Here we present a fully functional DIQRNG against the most general quantum adversaries [15][16][17]. We construct a robust experimental platform that realizes Bell inequality violation with entangled photons with detection and locality loopholes closed simultaneously. This platform enables a continuous recording of a large volume of data sufficient for security analysis against the general quantum side information and without assuming independent and identical distribution.Lastly, by developing a large Toeplitz matrix (137.90 Gb × 62.469 Mb) hashing technique, we demonstrate that this DIQRNG generates 6.2469 × 10 7 quantum-certified random bits in 96 hours (or 181 bits/s) with uniformity within 10 −5 . We anticipate this DIQRNG may have profound impact on the research of quantum randomness and information-secured applications.

A new class of fullerene bis-adductsdi(4-methylphenyl)methano-C60 bis-adduct (DMPCBA), di(4-fluorophenyl)methano-C60 bis-adduct (DFPCBA), and diphenylmethano-C60 bis-adduct (DPCBA)were rationally designed and easily synthesized. Compared to the lowest unoccupied molecular orbital (LUMO) energy level of PC61BM (−3.95 eV), the double functionalization effectively raises the LUMO energy levels of these fullerene materials to ca. −3.85 eV, regardless of the substituent groups (CH3–, F–, and H−) at the para-position of the phenyl rings. This phenomenon suggests that the plane of the phenyl groups is preferentially parallel to the fullerene surface, leading to poor orbital interactions with C60 and negligible electronic effect. Importantly, such geometry sterically protects and shields the core C60 structure from severe intermolecular aggregation, rendering it intrinsically soluble, morphologically amorphous, and thermally stable. The device based on the P3HT:DMPCBA blend exhibited an open-circuit voltage (V oc) of 0.87 V, a short-circuit current density (J sc) of 9.05 mA/cm2, and a fill factor (FF) of 65.5%, leading to a high power conversion efficiency (PCE) of 5.2%, which is superior to that of the P3HT:PC61BM-based device. Most significantly, the amorphous nature of DMPCBA effectively suppresses the thermal-driven aggregation and thus stabilizes the morphology of the P3HT:DMPCBA blend. Consequently, the device retained 80% of its original PCE value against thermal heating at 160 °C over 20 h.

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Inspired by the recent remarkable progress in the experimental test of local realism, we report here such a test that achieves an efficiency greater than (78%)^{2} for entangled photon pairs separated by 183 m. Further utilizing the randomness in cosmic photons from pairs of stars on the opposite sides of the sky for the measurement setting choices, we not only close the locality and detection loopholes simultaneously, but also test the null hypothesis against local hidden variable mechanisms for events that took place 11 years ago (13 orders of magnitude longer than previous experiments). After considering the bias in measurement setting choices, we obtain an upper bound on the p value of 7.87×10^{-4}, which clearly indicates the rejection with high confidence of potential local hidden variable models. One may further push the time constraint on local hidden variable mechanisms deep into the cosmic history by taking advantage of the randomness in photon emissions from quasars with large aperture telescopes.

shown that ion migration is an inherent property of perovskite. [8][9][10][11] When discussing perovskites, due to their soft lattice feature, weak chemical bonds and low defect formation energy are generally considered. For the ABX 3 perovskites, A-site ions (methylamium ions (MA + ) and formamidium ions (FA + )), B-site ions (lead ions (Pb 2+ ) and tin ions (Sn 2+ )), and X-site ions (iodide ions (I − ), bromide ions (Br − ), chloride ions (Cl − ), and other halogen ions) have low activation barrier and high diffusion coefficient. [3] These ionic defects within the lattice are easily activated to cause severe ion migration in the perovskite films under external factors. In fact, in addition to the internal ions of perovskite, ions introduced from the ambient atmosphere also have the potential to migrate. [12] To detect the effects of ion migration, abnormal phenomenon in perovskite were given attention. Snaith et al. first reported the abnormal photocurrent-voltage hysteresis phenomenon, which was that forward and reverse scan J-V curves can't overlap in PSCs. [13] Electric field-driven ion migration was considered to be the key factor to affect photocurrent hysteresis. Xiao et al. [14] reported the switchable photovoltaic effect in a plane heterojunction structure with symmetric electrodes, in which the current direction could be completely overturned. Ion migration was speculated to be the main cause. The reason for this inference is that the migration as well as the accumulation of ions can change the intrinsic electric field of the perovskite films, even causing local crystal structure changes, which in turn lead to further degradation of the PSCs and severely affect the operating stability. [15,16] Apart from these, ion migration can also cause slow photoconductivity response, halide redistribution, and segregation. [17] In order to push the commercialization step of PSCs, a clear understanding of the ion migration in OIHPs is meaningful and highly desired. Although some reports have reviewed the ion migration in OIHPs, [18][19][20] the explanation of the mechanisms behind ion migration is still incomplete and is usually introduced directly from theoretical calculations. Meanwhile, more reviews only focused on the ion migration in PSCs; ion migration in fact has profound implications for many other applications of perovskite materials, like photodetector, light emitting diodes, and random access memories. The use of low-dimensional materials to inhibit ion migration is an effective strategy, but the various species involved are not discussed in detail. What's more, the study of ion migration is quickly Organic-inorganic hybrid perovskite (OIHPs) solar cells are the most promising alternatives to traditional silicon solar cells, with a certified power conversion efficiency beyond 25%. However, the poor stability of OHIPs is one of the thorniest obstacles that hinder its commercial development. Among all the factors affecting stability, ion migration is prominent because it is unavoidable and intrinsic in OH...

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Let the sun shine in: Highly efficient and stable polymer bulk‐heterojunction solar cells can be achieved by the incorporation of vertically oriented, cross‐linked polymer nanorods (see picture). The device exhibits a record power conversion efficiency of 7.3 %.

We have developed two nitrogen-bridged pentacyclic donor–acceptor dithienopyrrolobenzothiadiazole (DTPBT) and dithienopyrroloquinoxaline (DTPQX) arenes where the two outer electron-rich thiophene moieties are covalently fastened with the central electron-deficient benzothiadiazole and quinoxaline cores by two nitrogen bridges. These rigid and coplanar DTPBT and DTPQX building blocks were copolymerized with fluorene (F), carbazole (C) and cyclopentadithiophene (CPDT) units via Suzuki or Stille coupling polymerization to afford six new alternating copolymers PFDTPBT, PCDTPBT, PCPDTDTPBT, PFDTPQX, PCDTPQX and PCPDTDTPQX, respectively. The nitrogen bridges not only planarize the structure to induce stronger intermolecular π–π interaction but also play an important role in determining the electronic and photophysical properties of the polymers. The device based on PFDTPQX/PC71BM (1:4, w/w) exhibited a open-circuit voltage (V oc) of 0.72 V, a short-circuit current (J sc) of 8.62 mA/cm2 and a FF of 0.55 leading to a decent power conversion efficiency (PCE) of 3.40% due to the lower-lying HOMO energy level, and the highest hole-mobility of PFDTPQX.