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1.
J Phys Condens Matter ; 34(35)2022 Jun 30.
Article in English | MEDLINE | ID: mdl-35709718

ABSTRACT

The review is devoted to the fundamental aspects and characteristic features of the magnetoelectric effects, reported in the literature on Josephson junctions (JJs). The main focus of the review is on the manifestations of the direct and inverse magnetoelectric effects in various types of Josephson systems. They provide a coupling of the magnetization in superconductor/ferromagnet/superconductor JJs to the Josephson current. The direct magnetoelectric effect is a driving force of spin torques acting on the ferromagnet inside the JJ. Therefore it is of key importance for the electrical control of the magnetization. The inverse magnetoelectric effect accounts for the back action of the magnetization dynamics on the Josephson subsystem, in particular, making the JJ to be in the resistive state in the presence of the magnetization dynamics of any origin. The perspectives of the coupling of the magnetization in JJs with ferromagnetic interlayers to the Josephson current via the magnetoelectric effects are discussed.

2.
Phys Rev Lett ; 128(16): 167701, 2022 Apr 22.
Article in English | MEDLINE | ID: mdl-35522505

ABSTRACT

A conventional superconductor sandwiched between two ferromagnets can maintain coherent equilibrium spin current. This spin supercurrent results from the rotation of odd-frequency spin correlations induced in the superconductor by the magnetic proximity effect. In the absence of intrinsic magnetization, the superconductor cannot maintain multiple rotations of the triplet component but instead provides a Josephson type weak link for the spin supercurrent. We determine the analog of the current-phase relation in various circumstances and show how it can be accessed in experiments on dynamic magnetization. In particular, concentrating on the magnetic hysteresis and the ferromagnetic resonance response, we show how the spin supercurrent affects the nonequilibrium dynamics of magnetization which depends on a competition between spin supercurrent mediated static exchange contribution and a dynamic spin pumping contribution. Depending on the outcome of this competition, a mode crossing in the system can either be an avoided crossing or mode locking.

3.
Phys Rev Lett ; 127(14): 147701, 2021 Oct 01.
Article in English | MEDLINE | ID: mdl-34652200

ABSTRACT

Dynamic states offer extended possibilities to control the properties of quantum matter. Recent efforts are focused on studying the ordered states which appear exclusively under the time-dependent drives. Here, we demonstrate a class of systems which feature dynamic spin-triplet superconducting order stimulated by the alternating electric field. The effect is based on the interplay of ferromagnetism, interfacial spin-orbital coupling, and the condensate motion driven by the field, which converts hidden static p-wave order, produced by the joint action of the ferromagnetism and the spin-orbital coupling, into dynamic s-wave equal-spin-triplet correlations. We demonstrate that the critical current of Josephson junctions hosting these states is proportional to the electromagnetic power, supplied either by the external irradiation or by the ac current source. Based on these unusual properties we propose the scheme of a Josephson transistor which can be switched by the ac voltage and demonstrates an even-numbered sequence of Shapiro steps. Combining the photoactive Josephson junctions with recently discovered Josephson phase batteries we find photomagnetic SQUID devices which can generate spontaneous magnetic fields while being exposed to irradiation.

4.
Phys Rev Lett ; 123(20): 207001, 2019 Nov 15.
Article in English | MEDLINE | ID: mdl-31809065

ABSTRACT

We describe resistive states of the system combining two types of orderings-a superconducting and a ferromagnetic one. It is shown that in the presence of magnetization dynamics such systems become inherently dissipative and in principle cannot sustain any amount of the superconducting current because of the voltage generated by the magnetization dynamics. We calculate generic current-voltage characteristics of a superconductor-ferromagnet-superconductor Josephson junction with an unpinned domain wall and find the low-current resistance associated with the domain wall motion. We suggest the finite slope of Shapiro steps as the characteristic feature of the regime with domain wall oscillations driven by the ac external current flowing through the junction.

5.
Phys Rev Lett ; 115(23): 235301, 2015 Dec 04.
Article in English | MEDLINE | ID: mdl-26684121

ABSTRACT

We study the spectrum of fermion states localized within the vortex core of a weak-coupling p-wave superfluid. The low energy spectrum consists of two anomalous branches that generate a large density of states at the locations of the half cores of the vortex. Fermi liquid interactions significantly stretch the vortex structure, which leads to a Lifshitz transition in the effective Fermi surface of the vortex core fermions. We apply the results to the rotational dynamics of vortices in superfluid ^{3}He-B and find an explanation for the observed slow mode.

6.
Ter Arkh ; 87(7): 64-71, 2015.
Article in Russian | MEDLINE | ID: mdl-26390727

ABSTRACT

AIM: To study the clinical features of Castleman's disease (CD) and to elaborate therapeutic approaches in its different morphological types. SUBJECTS AND METHODS: The clinical and laboratory data were studied in 59 prospectively examined patients and 17 retrospectively examined ones with CD who had been treated at the Outpatient Department, Hematology Research Centre, in 1996 to 2014. There were a total of 37 men (median age, 36 years) and 39 women (median age, 34 years). The diagnosis was established from the results of histological and immunohistochemical examinations of removed lymph nodes (LN) or tumors in all the cases. RESULTS: A hyaline vascular variant (HVV) with local LN involvement was diagnosed in 38 (50%) patients; a plasma cell variant (PCV) was in 38 (50%); among the latter, 17 (22%) patients were found to have local involvement and 21 (28%) had generalized (multicentriC) involvement (multicentric Castleman's diseases (MCD)). Five (24%) patients with MCD were established to be infected with human herpesvirus type 8 (HHV-8). HVV was more frequently diagnosed in women (4%) than in men (29%); PCV was equally common in both men (47%) and women (53%); MCD was statistically significantly more frequently encountered in men (86%) than in women (14%) (p=0.05). The basic involvement areas in local HVV and PCV were peripheral (38%), mediastinal (29), retroperitoneal (18%), abdominal (9%), and small pelvic (6%) LNs. HVV and local PCV were benign and these were cured by surgical removal of LNs involved in the pathological process. MCD took its aggressive course with obvious constitutional symptoms, generalized lymphadenopathy, hepatosplenomegaly, hypergammaglobulinemia, autoimmune hemolysis, thrombocytopenia, and involvement of extranodal foci in the pathological process. MCD transformation to plasmablastic lymphoma was observed in 4 of the 5 HHV8-positive patients and followed by a poor outcome. The prognosis of untreated MCD was unfavorable. In a number of cases prednisolone monotherapy worsened prognosis and the MCD patients receiving timely multiple-drug R-CHOP or R-VD chemotherapy could achieve sustained remission (the 5-year overall survival was 55%). CONCLUSION: CD must be included into the differential diagnosis of lymphadenopathies. When specific treatment is performed, the prognosis of HVV and local PCV is favorable: the disease is surgically cured in 95% of cases. Multidrug chemotherapy according to the B-cell lymphoproliferative disease program is indicated for the treatment of MCD: sustained remission can be achieved by the use of R-CHOP or R-VD programs. The HHV-8-positive variants of MCD increase the probability of transforming the disease to incurable plasmablastic lymphoma. Overall, prognosis and therapy choice in HIV-negative patients with CD depend on the histological variant of the disease, the extent of a tumor, and HHV-8 infection.


Subject(s)
Castleman Disease/diagnosis , Lymph Nodes/pathology , Adult , Aged , Diagnosis, Differential , Female , Humans , Male , Middle Aged , Prognosis , Retrospective Studies , Young Adult
8.
J Phys Condens Matter ; 26(9): 095702, 2014 Mar 05.
Article in English | MEDLINE | ID: mdl-24525668

ABSTRACT

On the basis of the phenomenological Ginzburg-Landau model we calculate the critical current of the domain-wall superconducting channel formed in flux-coupled superconductor/ferromagnet (S/F) hybrids in the presence of the nonuniform magnetic field of the domain walls. It is shown that the current-carrying ability in such S/F systems in the domain-wall superconducting state differs for the positive and negative directions of the injected current with respect to the parity-breaking vector, which is proportional to V x M and thus determined by the local magnetization vector M(r) in the ferromagnetic substrate. We demonstrate that in such S/F systems the realization of the so-called diode effect is possible for both laterally infinite and mesoscopic structures.

9.
Eksp Klin Gastroenterol ; (11): 51-6, 2014.
Article in Russian | MEDLINE | ID: mdl-25842665

ABSTRACT

Different tactical approaches present to optimize surgical treatment of patients with malignant tumors hepatopancreatoduodenal zone. This research based on diagnosis and results of treatment of tumors of this localization, which included 357 analyzed case histories of patients treated in the Chelyabinsk Regional Hospital from 2010 to 2014. During this study was considered the preoperative preparation of patients with malignant obstructive jaundice genesis, and was assessed its impact on the level of postoperative complications and mortality. Farther was found effectiveness of a two-stage surgical treatment of patients with obstructive jaundice malignant etiology for the reduction of postoperative mortality. The complication rate is significantly reduced radically operated patients with bilirubin level below 40 mmol/l, palliative - 80 mmol/l. Also were presented results of treatment of chronic pain.


Subject(s)
Biliary Tract Neoplasms/surgery , Duodenal Neoplasms/surgery , Pancreatic Neoplasms/surgery , Preoperative Care/methods , Biliary Tract Neoplasms/diagnosis , Biliary Tract Neoplasms/mortality , Decompression, Surgical/methods , Duodenal Neoplasms/diagnosis , Duodenal Neoplasms/mortality , Female , Hepatectomy/methods , Humans , Male , Middle Aged , Palliative Care , Pancreatic Neoplasms/diagnosis , Pancreatic Neoplasms/mortality , Pancreaticoduodenectomy/methods , Survival Analysis
11.
Ter Arkh ; 85(8): 69-76, 2013.
Article in Russian | MEDLINE | ID: mdl-24137967

ABSTRACT

AIM: To evaluate the clinical and hematologic efficiency of splenectomy (SE) in patients with myelofibrosis (MF) resistant to conventional traditional treatment. SUBJECTS AND METHODS: Case histories were retrospectively analyzed in 52 MF patients who had been followed up at the Hematology Research Center, Ministry of Health of the Russian Federation, in 2004 to 2012 and undergone therapeutic SE (47 patients with primary myelofibrosis, 4 with postpolycythemia myelofibrosis, and 1 with postthrombocythemia myelofibrosis). The mean age was 47 years at diagnosis and 53 years before surgery. The patients younger than 50 years of age constituted 60%. Massive and giant splenomegaly was detected in 37 (71%) patients. The spleen weighing 0.9 to 2.9 and 3 to 7 kg was removed in 15 (29%) and 35 (67%) patients, respectively. In 2 cases, the weight of the removed spleen was as much as 10 and 11 kg. RESULTS: By the moment of SE, the disease duration averaged 76 (from 1 to 240) months. Twenty-one (40%) patients developed perioperative complications, including bleeding (15%), thrombosis (11.5%), and infectious complications (13.5%). There were no deaths from surgical interventions in the intra- and early postoperative periods. In more than 80% of the patients after SE, their general condition improved and the symptoms of intoxication disappeared; in the majority of patients, the therapeutic effect lasted about 2 years. In the follow-up period, 33 (63%) patients died; the time to death averaged 27 (1-84) months following SE. The causes of death were blast transformation in 27 (82%) patients and comorbidity in 6 (18%); 19 (37%) patients with an average post-SE follow-up of 37 (4-72) months continued hydroxyurea treatment. The median survival after SE was equal to 3 years; the median overall survival was 11 years. CONCLUSION: SE is effective palliative care with an acceptable level of occurring complications for individual patients with MF. Contraindications to SE as blast crisis and severe comorbidities should be strictly taken into account.


Subject(s)
Intraoperative Complications , Postoperative Complications , Primary Myelofibrosis/surgery , Splenectomy/methods , Splenomegaly/surgery , Adult , Aged , Female , Humans , Kaplan-Meier Estimate , Male , Middle Aged , Palliative Care , Primary Myelofibrosis/complications , Primary Myelofibrosis/mortality , Retrospective Studies , Splenectomy/adverse effects , Splenectomy/mortality , Splenomegaly/etiology , Splenomegaly/mortality , Treatment Outcome
12.
J Phys Condens Matter ; 25(22): 225702, 2013 Jun 05.
Article in English | MEDLINE | ID: mdl-23673423

ABSTRACT

We investigate the multiquantum vortex states in a type-II superconductor in both 'clean' and 'dirty' regimes defined by impurity scattering rate. Within a quasiclassical approach we calculate self-consistently the order parameter distributions and electronic local density of states (LDOS) profiles. In the clean case we find the low temperature vortex core anomaly predicted analytically by Volovik (1993 JETP Lett. 58 455) and obtain the patterns of LDOS distributions. In the dirty regime multiquantum vortices feature a peculiar plateau in the zero energy LDOS profile, which can be considered as an experimental hallmark of multiquantum vortex formation in mesoscopic superconductors.

14.
Khirurgiia (Mosk) ; (8): 55-9, 2012.
Article in Russian | MEDLINE | ID: mdl-22968559

ABSTRACT

By large and giant volume of the spleen the mainstay of the surgery remains the open splenectomy. Splenomegaly stipulates certain difficulties and dangers of the procedure, mainly because the lack of the free space in the abdominal cavity. The maximally wide access, preliminary preparation and ligation of the splenic artery in situ and thorough separation of the spleen and pancreatic tail provide the safety and success of the operation. 374 splenectomies on the reason of the splenomegaly were analyzed. The standardization of the technique allowed the 2.5 times reduction of the postoperative complication rate (from 26.9 to 10.8%); the 1.8 times reduction of the intraoperative complication rate and the 17% reduction of the intraoperative blood loss. The postoperative pancreatitis was registered 4 times rare; the intraabdominal bleeding - 2 times rare and the frequency of the subphrenic abscess was 1.5 times lesser.


Subject(s)
Hematologic Diseases/complications , Splenectomy/methods , Splenomegaly/surgery , Adolescent , Adult , Aged , Aged, 80 and over , Blood Loss, Surgical/prevention & control , Female , Follow-Up Studies , Hematologic Diseases/diagnosis , Humans , Incidence , Laparotomy , Male , Middle Aged , Postoperative Hemorrhage/epidemiology , Postoperative Hemorrhage/prevention & control , Retrospective Studies , Russia/epidemiology , Severity of Illness Index , Splenic Artery/surgery , Splenomegaly/diagnosis , Splenomegaly/etiology , Treatment Outcome , Young Adult
15.
Ter Arkh ; 82(7): 72-5, 2010.
Article in Russian | MEDLINE | ID: mdl-20853614

ABSTRACT

The paper describes a rare case of formation of paravertebral extramedullary hemopoietic foci in microspherocytic anemia or Minkovsky-Shoffar disease in an adult. Therapeutic splenectomy has led to regression of extramedullary hemopoietic foci, which supports that there is a direct relationship of the above formations to the specific features of the etiology and pathogenesis of microspherocytic anemia.


Subject(s)
Choristoma/diagnosis , Hematopoiesis, Extramedullary , Mediastinal Diseases/diagnosis , Spherocytosis, Hereditary/diagnosis , Spherocytosis, Hereditary/surgery , Adult , Choristoma/pathology , Choristoma/surgery , Diagnosis, Differential , Humans , Male , Mediastinal Diseases/pathology , Mediastinal Diseases/surgery , Spherocytosis, Hereditary/pathology , Splenectomy , Thoracotomy , Thorax/pathology , Treatment Outcome
16.
Ter Arkh ; 81(7): 75-7, 2009.
Article in Russian | MEDLINE | ID: mdl-19708579

ABSTRACT

Literature gives only few reports of hyaline-vascular variant of Castleman's disease associated with tumor from dendritic cells. A case of simultaneous detection of these diseases in the tumor located in the retroperitoneal space and successfully removed surgically is reported.


Subject(s)
Castleman Disease/diagnosis , Castleman Disease/surgery , Dendritic Cells, Follicular/pathology , Hyalin , Castleman Disease/pathology , Humans , Male , Middle Aged , Treatment Outcome
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