File Download

There are no files associated with this item.

  Links for fulltext
     (May Require Subscription)
Supplementary

Article: A theoretical search for possible high efficiency semiconductor based field assisted positron moderators

TitleA theoretical search for possible high efficiency semiconductor based field assisted positron moderators
Authors
Issue Date1999
PublisherElsevier BV. The Journal's web site is located at http://www.elsevier.com/locate/apsusc
Citation
Applied Surface Science, 1999, v. 149 n. 1, p. 253-259 How to Cite?
AbstractThe need to obtain more intense positron beams is an ever-pressing concern in experimental positron physics. The present paper explores one route of obtaining better conversion efficiencies, namely by use of the field assisted positron technique. The basic principles of field assisted moderation are first reviewed. Theoretical estimates of possible expected positron yields from various semiconductor based field assisted moderators are then presented, the general aim being to give some guidance to experimentalists seeking to test such potential moderator systems. The calculations are based on positron affinities calculated using density functional ab initio pseudopotential theory and are found to be in good accord with experimental data where such exist. The work suggests that wide-gap materials such as GaN, C and SiC tend to compress the positron wavefunction leading to higher energy positron band states that favor positron emission. However, these materials also suffer from short positron lifetimes and low densities. In contrast, materials such as GaP, GaAs and ZnSe are also favored as positron emitters albeit with lower emission energy, but these materials have the advantage of longer lifetimes and higher densities that favor more efficient moderation.
Persistent Identifierhttp://hdl.handle.net/10722/174776
ISSN
2015 Impact Factor: 3.15
2015 SCImago Journal Rankings: 0.930
References

 

DC FieldValueLanguage
dc.contributor.authorBeling, CDen_HK
dc.contributor.authorFung, Sen_HK
dc.contributor.authorMing, Lien_HK
dc.contributor.authorGong, Men_HK
dc.contributor.authorPanda, BKen_HK
dc.date.accessioned2012-11-26T08:47:23Z-
dc.date.available2012-11-26T08:47:23Z-
dc.date.issued1999en_HK
dc.identifier.citationApplied Surface Science, 1999, v. 149 n. 1, p. 253-259en_HK
dc.identifier.issn0169-4332en_HK
dc.identifier.urihttp://hdl.handle.net/10722/174776-
dc.description.abstractThe need to obtain more intense positron beams is an ever-pressing concern in experimental positron physics. The present paper explores one route of obtaining better conversion efficiencies, namely by use of the field assisted positron technique. The basic principles of field assisted moderation are first reviewed. Theoretical estimates of possible expected positron yields from various semiconductor based field assisted moderators are then presented, the general aim being to give some guidance to experimentalists seeking to test such potential moderator systems. The calculations are based on positron affinities calculated using density functional ab initio pseudopotential theory and are found to be in good accord with experimental data where such exist. The work suggests that wide-gap materials such as GaN, C and SiC tend to compress the positron wavefunction leading to higher energy positron band states that favor positron emission. However, these materials also suffer from short positron lifetimes and low densities. In contrast, materials such as GaP, GaAs and ZnSe are also favored as positron emitters albeit with lower emission energy, but these materials have the advantage of longer lifetimes and higher densities that favor more efficient moderation.en_HK
dc.languageengen_US
dc.publisherElsevier BV. The Journal's web site is located at http://www.elsevier.com/locate/apsuscen_HK
dc.relation.ispartofApplied Surface Scienceen_HK
dc.titleA theoretical search for possible high efficiency semiconductor based field assisted positron moderatorsen_HK
dc.typeArticleen_HK
dc.identifier.emailBeling, CD: cdbeling@hkucc.hku.hken_HK
dc.identifier.emailFung, S: sfung@hku.hken_HK
dc.identifier.authorityBeling, CD=rp00660en_HK
dc.identifier.authorityFung, S=rp00695en_HK
dc.description.naturelink_to_subscribed_fulltexten_US
dc.identifier.doi10.1016/S0169-4332(99)00211-1en_HK
dc.identifier.scopuseid_2-s2.0-0032681520en_HK
dc.identifier.hkuros47342-
dc.relation.referenceshttp://www.scopus.com/mlt/select.url?eid=2-s2.0-0032681520&selection=ref&src=s&origin=recordpageen_HK
dc.identifier.volume149en_HK
dc.identifier.issue1en_HK
dc.identifier.spage253en_HK
dc.identifier.epage259en_HK
dc.publisher.placeNetherlandsen_HK
dc.identifier.scopusauthoridBeling, CD=7005864180en_HK
dc.identifier.scopusauthoridFung, S=7201970040en_HK
dc.identifier.scopusauthoridMing, Li=7102986091en_HK
dc.identifier.scopusauthoridGong, M=9273057400en_HK
dc.identifier.scopusauthoridPanda, BK=22963418500en_HK

Export via OAI-PMH Interface in XML Formats


OR


Export to Other Non-XML Formats