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Löb P, Hessel V, Menges G, Vankayala BK, Metzke D, Hofmann C. Charakterisierung eines Mikrofallfilmreaktors für den Pilotanlagenbetrieb. CHEM-ING-TECH 2007. [DOI: 10.1002/cite.200750383] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
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Wichmann D, Hofmann C, Sudeck H, Burchard GD, Moser A. Myeloradiculitis: a rare event in schistosoma infection. Infection 2007; 34:349-51. [PMID: 17180592 DOI: 10.1007/s15010-006-5116-6] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/25/2005] [Accepted: 02/20/2006] [Indexed: 11/28/2022]
Abstract
Schistosomiasis a parasitic disease caused by trematodes is widely distributed in (sub-)tropical countries. Depending on the species the infection manifests clinically as gastrointestinal (preferentially Schistosoma mansoni and S. japonicum) or urinary (preferentially S. haematobium) disorders. Here we present an uncommon case of myeloradiculitis leading to bladder palsy and sensory loss at the lower limbs.
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Hofmann C, Sambade A, Heinlein M. Plasmodesmata and intercellular transport of viral RNA. Biochem Soc Trans 2007; 35:142-5. [PMID: 17233621 DOI: 10.1042/bst0350142] [Citation(s) in RCA: 37] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
Cell-to-cell communication in plants involves the symplastic trafficking of informational protein and RNA macromolecules through cytoplasmic bridges in the plant cell wall known as plasmodesmata. Viruses exploit this route for the spread of infection and are used as a model to study the mechanisms by which macromolecules are targeted to the pore. Studies using tobacco mosaic virus have led to the identification of host components that participate in plasmodesmal targeting of viral RNA and movement protein.
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Hessel V, Hofmann C, Löb P, Löwe H, Parals M. Microreactor Processing for the Aqueous Kolbe-Schmitt Synthesis of Hydroquinone and Phloroglucinol. Chem Eng Technol 2007. [DOI: 10.1002/ceat.200600245] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
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Riecken S, Schmidt H, Darcan Y, Janssen O, Becker W, Adler HS, Christ S, Raps C, Hofmann C, Scheurer S, Vieths S, Steinbrink K, Ilchmann A, Waibler Z, Kalinke U, Toda M, Hompes S, Behrendt N, Schoepke N, Dölle S, Zuberbier T, Worm M, Dolle S, Fiedler E. Nahrungsmittel/Gastrointestinaltrakt. ALLERGO JOURNAL 2007. [DOI: 10.1007/bf03370559] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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Ulrich SM, Gies C, Ates S, Wiersig J, Reitzenstein S, Hofmann C, Löffler A, Forchel A, Jahnke F, Michler P. Photon statistics of semiconductor microcavity lasers. PHYSICAL REVIEW LETTERS 2007; 98:043906. [PMID: 17358772 DOI: 10.1103/physrevlett.98.043906] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/02/2006] [Indexed: 05/14/2023]
Abstract
We present measurements of first- and second-order coherence of quantum-dot micropillar lasers together with a semiconductor laser theory. Our results show a broad threshold region for the observed high-beta microcavities. The intensity jump is accompanied by both pronounced photon intensity fluctuations and strong coherence length changes. The investigations clearly visualize a smooth transition from spontaneous to predominantly stimulated emission which becomes harder to determine for high beta. In our theory, a microscopic approach is used to incorporate the semiconductor nature of quantum dots. The results are in agreement with the experimental intensity traces and the photon statistics measurements.
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Dietlein M, Grünerbel A, Merke J, Karagiannis E, Bierwirth RA, Hofmann C, Franzen C, Lübben G. Wirkung von Pioglitazon auf die Intima-Media-Dicke (IMT) der Arteria carotis und auf metabolische Parameter bei Patienten mit Typ-2-Diabetes Mellitus. DIABETOL STOFFWECHS 2007. [DOI: 10.1055/s-2007-982268] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/21/2022]
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Bierwirth RA, Merke J, Grünerbel A, Hofmann C, Dietlein M, Franzen C, Karagiannis E, Lübben G. Pioglitazon reduziert die Intima-Media-Dicke (IMT) der Arteria carotis bei Patienten mit Typ-2-Diabetes Mellitus. DIABETOL STOFFWECHS 2007. [DOI: 10.1055/s-2007-982409] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/21/2022]
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Briegel W, Hofmann C, Schwab KO. Moebius sequence: behaviour problems of preschool children and parental stress. GENETIC COUNSELING (GENEVA, SWITZERLAND) 2007; 18:267-275. [PMID: 18019367] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 05/25/2023]
Abstract
This study investigates behaviour problems of preschool children with Moebius sequence, and their primary caregivers' stress. To this end, parents of all preschool children with Moebius sequence known to the German Moebius foundation were anonymously asked to fill out questionnaires, e.g. the Child Behavior Checklist [CBCL] 1.5-5. The primary caregivers of 13/22 children (seven males, six females; mean age: 3;10 [2;1-5;11] years) sent back filled-out questionnaires. Two children were rated as clinical on the CBCL-1.5-5. Boys had significantly higher scores on the scales aggressive behavior and total problems than girls. Compared to the general population, but not to other parents of mentally and / or physically handicapped children, the primary caregivers experienced higher levels of stress. In conclusion, preschool children with Moebius sequence do not show essentially increased rates of clinical behaviour problems. Nevertheless, their primary caregivers experience increased stress and need early and adequate support.
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Hofmann C, Artinger M, Grossmann J, Schölmerich J, Rogler G, Obermeier F. Einfluss von Zell-Zell-Kontakten auf das Überleben primärer humaner Kolonepithelzellen und die Regulation von Bcl-2-Proteinen. ZEITSCHRIFT FUR GASTROENTEROLOGIE 2006. [DOI: 10.1055/s-2006-955538] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/19/2022]
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Wirtz AC, Hofmann C, Groenen EJJ. Spin-Coated Polyethylene Films Probed by Single Molecules. J Phys Chem B 2006; 110:21623-9. [PMID: 17064117 DOI: 10.1021/jp0642894] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
We have studied ultrathin spin-coated high-density polyethylene films by means of single-molecule spectroscopy and microscopy at 1.8 K. The films have been doped with 2.3,8.9-dibenzanthanthrene (DBATT) molecules, which function as local reporters of their immediate environment. The orientation distributions of single DBATT probe molecules in 100-200 nm thin films of high-density polyethylene differ markedly from those in low-density films. We have found a preferential orientation of dopant molecules along two well-defined, mutually perpendicular directions. These directions are preserved over at least a 2 mm distance. The strong orientation preference of the probe molecules requires the presence of abundant lateral crystal faces and is therefore not consistent with a spherulitic morphology. Instead, a "shish-kebab" crystal structure is invoked to explain our results.
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Löb P, Hessel V, Menges G, Vankayala B, Metzke D, Hofmann C. Gas/Flüssig-Kontaktierung in Mikrofallfilmreaktoren im Pilot- und Produktionsmaßstab. CHEM-ING-TECH 2006. [DOI: 10.1002/cite.200650295] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
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Löb P, Hessel V, Men Y, Hollomotz S, Hofmann C. Flüssig/Flüssig-Dispergierung in verschiedenen Mikromischertypen. CHEM-ING-TECH 2006. [DOI: 10.1002/cite.200650298] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
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Bihlmaier C, Welle E, Hofmann C, Welzel K, Vente A, Breitling E, Müller M, Glaser S, Bechthold A. Biosynthetic gene cluster for the polyenoyltetramic acid alpha-lipomycin. Antimicrob Agents Chemother 2006; 50:2113-21. [PMID: 16723573 PMCID: PMC1479109 DOI: 10.1128/aac.00007-06] [Citation(s) in RCA: 61] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
The gram-positive bacterium Streptomyces aureofaciens Tü117 produces the acyclic polyene antibiotic alpha-lipomycin. The entire biosynthetic gene cluster (lip gene cluster) was cloned and characterized. DNA sequence analysis of a 74-kb region revealed the presence of 28 complete open reading frames (ORFs), 22 of them belonging to the biosynthetic gene cluster. Central to the cluster is a polyketide synthase locus that encodes an eight-module system comprised of four multifunctional proteins. In addition, one ORF shows homology to those for nonribosomal peptide synthetases, indicating that alpha-lipomycin belongs to the classification of hybrid peptide-polyketide natural products. Furthermore, the lip cluster includes genes responsible for the formation and attachment of d-digitoxose as well as ORFs that resemble those for putative regulatory and export functions. We generated biosynthetic mutants by insertional gene inactivation. By analysis of culture extracts of these mutants, we could prove that, indeed, the genes involved in the biosynthesis of lipomycin had been cloned, and additionally we gained insight into an unusual biosynthesis pathway.
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Reitzenstein S, Löffler A, Hofmann C, Kubanek A, Kamp M, Reithmaier JP, Forchel A, Kulakovskii VD, Keldysh LV, Ponomarev IV, Reinecke TL. Coherent photonic coupling of semiconductor quantum dots. OPTICS LETTERS 2006; 31:1738-40. [PMID: 16688279 DOI: 10.1364/ol.31.001738] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/09/2023]
Abstract
We report a new type of coupling between quantum dot excitons mediated by the strong single-photon field in a high-finesse micropillar cavity. Coherent exciton coupling is observed for two dots with energy differences of the order of the exciton-photon coupling. The coherent coupling mode is characterized by an anticrossing with a particularly large line splitting of 250 microeV. Because of the different dispersion relations with temperature, the simultaneous photonic coupling of quantum dot excitons can be easily distinguished from cases of sequential strong coupling of two quantum dots.
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Hofmann C, Penner U, Dorow R, Pertz HH, Jähnichen S, Horowski R, Latté KP, Palla D, Schurad B. Lisuride, a dopamine receptor agonist with 5-HT2B receptor antagonist properties: absence of cardiac valvulopathy adverse drug reaction reports supports the concept of a crucial role for 5-HT2B receptor agonism in cardiac valvular fibrosis. Clin Neuropharmacol 2006; 29:80-6. [PMID: 16614540 DOI: 10.1097/00002826-200603000-00005] [Citation(s) in RCA: 73] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
OBJECTIVES The high incidence of fibrotic cardiac valvulopathies reported in association with the 8beta-ergoline dopamine (DA) agonist, pergolide, and also case reports for cabergoline and bromocriptine have made it necessary to review the theoretical basis and actual findings in the case of another DA agonist, the 8alpha-ergoline lisuride (used since the 1970s for migraine prophylaxis as well as since the 1980s for its prolactin-lowering and anti-Parkinson activity). METHODS We have reviewed the pharmacology of lisuride in relation to other DA agonists, and we have performed a throughout literature search as well as a search of our own and other adverse drug reaction databases for a possible relationship of lisuride with cardiac valvulopathy or for any reports of fibrosis in other locations. RESULTS Our review of the pharmacology and the literature strongly suggests that drug-induced cardiac valvulopathies are always related to a stimulatory drug effect on trophic 5-HT(2B) receptors. As lisuride is devoid of such an effect, but on the contrary is an extremely potent 5-HT(2B) antagonist, an association of lisuride therapy with cardiac valvulopathies seems to be highly unlikely. In agreement with this hypothesis, not a single report of a cardiac valvulopathy associated with lisuride therapy has been identified in any database so far.Furthermore, against a background of an estimated 360,000 patient years, we have found only a very small number of cases of any other form of fibrosis (1x retroperitoneal, 2x pleural, 2x pulmonary, 1x interstitial pulmonary changes), in part combined with other risk factors and confounding variables. This closely matches 4 reports available from WHO (1x retroperitoneal, 3x pleural fibrosis). In addition, only 5 other possibly related conditions (3x pleural effusion, 1x pleuritis, 1x pericarditis) were identified in the lisuride adverse drug reaction database of Schering, Berlin. CONCLUSIONS No link has been found between lisuride use and fibrotic cardiac valvulopathy, in agreement with the 5-HT(2B) receptor antagonist effect of this drug. The very low incidence of spontaneous reports of any other fibrosis could be even compatible with an association by chance in the population exposed to lisuride. Although close monitoring for this kind of side effects is still to be recommended in the therapy with lisuride, our data do not support the concept of a class effect suggesting that all ergot-derived drugs and especially DA receptor agonists with some chemical similarity to the ergot structure will cause or facilitate cardiac valvulopathies as observed with pergolide.
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Gupta AS, Wang S, Link E, Anderson EH, Hofmann C, Lewandowski J, Kottke-Marchant K, Marchant RE. Glycocalyx-mimetic dextran-modified poly(vinyl amine) surfactant coating reduces platelet adhesion on medical-grade polycarbonate surface. Biomaterials 2006; 27:3084-95. [PMID: 16460796 DOI: 10.1016/j.biomaterials.2006.01.002] [Citation(s) in RCA: 42] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/15/2005] [Accepted: 01/03/2006] [Indexed: 10/25/2022]
Abstract
A dextran-modified poly(vinyl amine) comb-like surfactant polymer, poly(N-vinyl dextran aldonamide-co-N-vinyl hexanamide), that can surface-adsorb on hydrophobic polymeric substrates, was designed to improve the interfacial blood-compatibility of polymeric biomaterials. Medical-grade polycarbonate was selected as a model substrate because of its extensive use in blood-contacting biomedical devices like hemodialyzers, blood pumps and oxygenators. The surfactant polymer was physisorbed from aqueous solution onto the polycarbonate substrate. The surfactant coating was stable under dynamic shear conditions in whole blood, as confirmed by fluorescence microscopy and total internal reflection fluorescence (TIRF) experiments with fluorescein-labeled surfactant polymer. The coated disks and uncoated control disks were exposed to platelet-rich plasma (PRP) and whole human blood in a rotating disk system (RDS) to study platelet-adhesion under dynamic shear stress environments. Adhered platelets were stained with fluorescein isothiocyante (FITC)-tagged anti-CD41a monoclonal antibody and imaged by epifluorescence microscopy. Complimentary images were obtained by phase-contrast microscopy. Platelet adhesion on the surfactant-coated disks was reduced by approximately 90%, compared with uncoated disks. The images also showed a concomitant reduction in platelet-derived microparticles on surfactant-coated disks, compared with uncoated disks. The results suggest potential application of carbohydrate-modified surfactant polymers as a glycocalyx-mimetic non-thrombogenic interfacial coating for blood-contacting biomaterials.
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Cominos V, Hessel V, Hofmann C, Kolb G, Zapf R, Ziogas A, Delsman E, Schouten J. Selective oxidation of carbon monoxide in a hydrogen-rich fuel cell feed using a catalyst coated microstructured reactor. Catal Today 2005. [DOI: 10.1016/j.cattod.2005.09.008] [Citation(s) in RCA: 33] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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69
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Hofmann C, Artinger M, Grossmann J, Schölmerich J, Rogler G, Obermeier F. Zell-Zell-Kontakte verhindern Anoikis in primären humanen Kolonepithelzellen durch Aktivierung des Epidermal Growth Factor Rezeptors (EGFR). ZEITSCHRIFT FUR GASTROENTEROLOGIE 2005. [DOI: 10.1055/s-2005-921794] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/19/2022]
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Jadcherla SR, Duong HQ, Hofmann C, Hoffmann R, Shaker R. Characteristics of upper oesophageal sphincter and oesophageal body during maturation in healthy human neonates compared with adults. Neurogastroenterol Motil 2005; 17:663-70. [PMID: 16185304 DOI: 10.1111/j.1365-2982.2005.00706.x] [Citation(s) in RCA: 89] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/08/2023]
Abstract
We evaluated the upper oesophageal sphincter (UOS) relationship with oesophageal body during primary peristalsis (PP) sequences in healthy human neonates during maturation and compared with that of healthy adult volunteers. Forty-nine studies were performed using a water perfusion manometry system and a specially designed oesophageal catheter with a UOS sleeve concurrent with submental electromyogram in 31 subjects in supine position (18 preterm neonates, 29.9 +/- 2.5 weeks gestation; four full-term neonates, 39.3 +/- 1.0 weeks gestation; and nine adults, 18-65 years). The preterm neonates were studied longitudinally at 33 and 36 weeks postmenstrual age (PMA) and full-term born at 40 weeks PMA. Data were compared between the groups to recognize the effects of gestation, postnatal age and ageing. We evaluated 403 consecutive spontaneous solitary swallows during maturation (preterm at time-1 vs time-2) and growth (preterm and full-term vs adults) and observed significant (P < 0.05) differences in the basal UOS resting pressure, UOS relaxation characteristics, proximal and distal oesophageal body amplitude, duration, propagation and peristaltic velocity. Characteristics of UOS and PP are well-developed by 33 weeks PMA and undergo further maturation during the postnatal period, and are significantly different from that of adult.
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Hessel V, Hofmann C, Löb P, Löhndorf J, Löwe H, Ziogas A. Aqueous Kolbe−Schmitt Synthesis Using Resorcinol in a Microreactor Laboratory Rig under High-p,T Conditions. Org Process Res Dev 2005. [DOI: 10.1021/op050045q] [Citation(s) in RCA: 72] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
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Kolb G, Cominos V, Hofmann C, Pennemann H, Schürer J, Tiemann D, Wichert M, Zapf R, Hessel V, Löwe H. Integrated Microstructured Fuel Processors for Fuel Cell Applications. Chem Eng Res Des 2005. [DOI: 10.1205/cherd.04357] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
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73
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Bechthold A, Weitnauer G, Luzhetskyy A, Berner M, Bihlmeier C, Boll R, Dürr C, Frerich A, Hofmann C, Mayer A, Treede I, Vente A, Luzhetskyy M. Glycosyltransferases and other tailoring enzymes as tools for the generation of novel compounds. ERNST SCHERING RESEARCH FOUNDATION WORKSHOP 2005:147-63. [PMID: 15645720 DOI: 10.1007/3-540-27055-8_7] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/01/2023]
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Reithmaier JP, Sek G, Löffler A, Hofmann C, Kuhn S, Reitzenstein S, Keldysh LV, Kulakovskii VD, Reinecke TL, Forchel A. Strong coupling in a single quantum dot–semiconductor microcavity system. Nature 2004; 432:197-200. [PMID: 15538362 DOI: 10.1038/nature02969] [Citation(s) in RCA: 438] [Impact Index Per Article: 21.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/11/2004] [Accepted: 08/26/2004] [Indexed: 11/09/2022]
Abstract
Cavity quantum electrodynamics, a central research field in optics and solid-state physics, addresses properties of atom-like emitters in cavities and can be divided into a weak and a strong coupling regime. For weak coupling, the spontaneous emission can be enhanced or reduced compared with its vacuum level by tuning discrete cavity modes in and out of resonance with the emitter. However, the most striking change of emission properties occurs when the conditions for strong coupling are fulfilled. In this case there is a change from the usual irreversible spontaneous emission to a reversible exchange of energy between the emitter and the cavity mode. This coherent coupling may provide a basis for future applications in quantum information processing or schemes for coherent control. Until now, strong coupling of individual two-level systems has been observed only for atoms in large cavities. Here we report the observation of strong coupling of a single two-level solid-state system with a photon, as realized by a single quantum dot in a semiconductor microcavity. The strong coupling is manifest in photoluminescence data that display anti-crossings between the quantum dot exciton and cavity-mode dispersion relations, characterized by a vacuum Rabi splitting of about 140 microeV.
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Löb P, Hessel V, Löwe H, Hofmann C. Bromierungsreaktionen in Mikromischer-Rohr-Reaktoren. CHEM-ING-TECH 2004. [DOI: 10.1002/cite.200490172] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
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