Pub Date : 2023-07-27eCollection Date: 2023-08-01DOI: 10.1515/nanoph-2023-0287
Stephan Rinner, Florian Burger, Andreas Gritsch, Jonas Schmitt, Andreas Reiserer
Quantum memories integrated into nanophotonic silicon devices are a promising platform for large quantum networks and scalable photonic quantum computers. In this context, erbium dopants are particularly attractive, as they combine optical transitions in the telecommunications frequency band with the potential for second-long coherence time. Here, we show that these emitters can be reliably integrated into commercially fabricated low-loss waveguides. We investigate several integration procedures and obtain ensembles of many emitters with an inhomogeneous broadening of <2 GHz and a homogeneous linewidth of <30 kHz. We further observe the splitting of the electronic spin states in a magnetic field up to 9 T that freezes paramagnetic impurities. Our findings are an important step toward long-lived quantum memories that can be fabricated on a wafer-scale using CMOS technology.
{"title":"Erbium emitters in commercially fabricated nanophotonic silicon waveguides.","authors":"Stephan Rinner, Florian Burger, Andreas Gritsch, Jonas Schmitt, Andreas Reiserer","doi":"10.1515/nanoph-2023-0287","DOIUrl":"10.1515/nanoph-2023-0287","url":null,"abstract":"<p><p>Quantum memories integrated into nanophotonic silicon devices are a promising platform for large quantum networks and scalable photonic quantum computers. In this context, erbium dopants are particularly attractive, as they combine optical transitions in the telecommunications frequency band with the potential for second-long coherence time. Here, we show that these emitters can be reliably integrated into commercially fabricated low-loss waveguides. We investigate several integration procedures and obtain ensembles of many emitters with an inhomogeneous broadening of <2 GHz and a homogeneous linewidth of <30 kHz. We further observe the splitting of the electronic spin states in a magnetic field up to 9 T that freezes paramagnetic impurities. Our findings are an important step toward long-lived quantum memories that can be fabricated on a wafer-scale using CMOS technology.</p>","PeriodicalId":7508,"journal":{"name":"African Affairs","volume":"15 1","pages":"3455-3462"},"PeriodicalIF":6.5,"publicationDate":"2023-07-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC10432618/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"83123264","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"社会学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Almost a decade after the 2011 post-electoral crisis, Côte d’Ivoire once again held elections marred by widespread violence. The third-term crisis revolved around President Alassane Ouattara’s controversial third-term bid and left at least 83 people dead and 633 people injured. This briefing draws on a new electoral violence dataset and field research to unpack patterns of violence during the crisis, and disentangles disruptive electoral violence related to the opposition’s campaign to thwart the election from incidental electoral violence related to the overall electoral tension. The findings show that incidental violence was far deadlier than disruptive violence, yet only tenuously related to the national political divide. This incidental violence was often driven by pre-existing local resource conflicts, revenge, rumours and disinformation, and elite manipulation. The briefing contributes new knowledge on the local drivers of electoral violence in Côte d’Ivoire, and cautions that viewing local communities only as victims of elite rivalries can make decision-makers overlook important risk factors.
{"title":"Patterns of electoral violence during Côte d’Ivoire’s third-Term crisis","authors":"S. van Baalen, Abel Gbala","doi":"10.1093/afraf/adad020","DOIUrl":"https://doi.org/10.1093/afraf/adad020","url":null,"abstract":"\u0000 Almost a decade after the 2011 post-electoral crisis, Côte d’Ivoire once again held elections marred by widespread violence. The third-term crisis revolved around President Alassane Ouattara’s controversial third-term bid and left at least 83 people dead and 633 people injured. This briefing draws on a new electoral violence dataset and field research to unpack patterns of violence during the crisis, and disentangles disruptive electoral violence related to the opposition’s campaign to thwart the election from incidental electoral violence related to the overall electoral tension. The findings show that incidental violence was far deadlier than disruptive violence, yet only tenuously related to the national political divide. This incidental violence was often driven by pre-existing local resource conflicts, revenge, rumours and disinformation, and elite manipulation. The briefing contributes new knowledge on the local drivers of electoral violence in Côte d’Ivoire, and cautions that viewing local communities only as victims of elite rivalries can make decision-makers overlook important risk factors.","PeriodicalId":7508,"journal":{"name":"African Affairs","volume":" ","pages":""},"PeriodicalIF":2.8,"publicationDate":"2023-07-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"49599587","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"社会学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Journal Article The agency problem in readings of Sino–African relations Get access Niall Duggan Niall Duggan Search for other works by this author on: Oxford Academic Google Scholar African Affairs, adad024, https://doi.org/10.1093/afraf/adad024 Published: 15 September 2023 Article history Accepted: 21 August 2023 Corrected and typeset: 15 September 2023 Published: 15 September 2023
{"title":"The agency problem in readings of Sino–African relations","authors":"Niall Duggan","doi":"10.1093/afraf/adad024","DOIUrl":"https://doi.org/10.1093/afraf/adad024","url":null,"abstract":"Journal Article The agency problem in readings of Sino–African relations Get access Niall Duggan Niall Duggan Search for other works by this author on: Oxford Academic Google Scholar African Affairs, adad024, https://doi.org/10.1093/afraf/adad024 Published: 15 September 2023 Article history Accepted: 21 August 2023 Corrected and typeset: 15 September 2023 Published: 15 September 2023","PeriodicalId":7508,"journal":{"name":"African Affairs","volume":"79 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-07-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"135807031","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"社会学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Abstract The recent Chinese involvement in small-scale gold mining in Ghana has received wide publicity and scholarly attention. While the literature has focused on environmental sustainability, political accountability, and institutional reforms, it is yet to examine local adoption of Chinese technology and its impact on Ghana’s rural economy. We argue that it is in the interstices between the formal economy and entrepreneurship within the informal economy that opportunities for Chinese interventions emerge. Using evidence from Manso Akropong in the Ashanti region and Bole in the Savannah region, this article shows that, while Chinese technology’s impact is transformative, the outcomes are divergent in different regions. In Manso Akropong, the intensification of mining backed by Ghanaian–Chinese collaborations has led to the environmental destruction, creating competition between gold mining and cocoa farming that had underpinned Ghana’s rural prosperity. In Bole, where less aggressive Chinese technology such as Changfa and rubber mats are incorporated without direct Chinese participation, a more sustainable pattern of growth has emerged. This comparative study suggests that besides the large-scale projects and state-led training programmes, grassroots actors like informal artisanal miners are at the forefront of technology transfer in the China–Africa encounter.
{"title":"Chinese technology and the transformation of the rural economy in Ghana: Evidence from <i>galamsey</i> in the ashanti and Savannah regions","authors":"Emmanuel Akyeampong, Liang Xu","doi":"10.1093/afraf/adad023","DOIUrl":"https://doi.org/10.1093/afraf/adad023","url":null,"abstract":"Abstract The recent Chinese involvement in small-scale gold mining in Ghana has received wide publicity and scholarly attention. While the literature has focused on environmental sustainability, political accountability, and institutional reforms, it is yet to examine local adoption of Chinese technology and its impact on Ghana’s rural economy. We argue that it is in the interstices between the formal economy and entrepreneurship within the informal economy that opportunities for Chinese interventions emerge. Using evidence from Manso Akropong in the Ashanti region and Bole in the Savannah region, this article shows that, while Chinese technology’s impact is transformative, the outcomes are divergent in different regions. In Manso Akropong, the intensification of mining backed by Ghanaian–Chinese collaborations has led to the environmental destruction, creating competition between gold mining and cocoa farming that had underpinned Ghana’s rural prosperity. In Bole, where less aggressive Chinese technology such as Changfa and rubber mats are incorporated without direct Chinese participation, a more sustainable pattern of growth has emerged. This comparative study suggests that besides the large-scale projects and state-led training programmes, grassroots actors like informal artisanal miners are at the forefront of technology transfer in the China–Africa encounter.","PeriodicalId":7508,"journal":{"name":"African Affairs","volume":"173 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-07-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"135805285","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"社会学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Kristian Hoelscher, Nick Dorward, Sean Fox, Taibat Lawanson, Jeffrey W Paller, Melanie L Phillips
Abstract Urbanization is transforming the human and political geography of Africa. While a growing body of research explores the urban dimensions of clientelism, contentious action, and social mobilization, there has been less attention given to the ways in which this demographic megatrend is influencing political change more broadly. We argue that the political implications of African urbanization are contingent on local conditions and experiences; there are no deterministic associations between urbanization and political change. To better understand the mechanisms linking urbanization to politics, we argue that a place-based approach is needed. We illustrate this by reviewing and highlighting how urbanization may affect (i) the nature and balance of citizen preferences; (ii) the composition, interests, and influence of elite actors; (iii) forms of political mobilization; (iv) shifting gender roles; (v) the role of civil society in political processes; and (vi) the likelihood and manifestations of contentious collective action. We conclude with a discussion of directions for further research.
{"title":"Urbanization and political change in Africa","authors":"Kristian Hoelscher, Nick Dorward, Sean Fox, Taibat Lawanson, Jeffrey W Paller, Melanie L Phillips","doi":"10.1093/afraf/adad021","DOIUrl":"https://doi.org/10.1093/afraf/adad021","url":null,"abstract":"Abstract Urbanization is transforming the human and political geography of Africa. While a growing body of research explores the urban dimensions of clientelism, contentious action, and social mobilization, there has been less attention given to the ways in which this demographic megatrend is influencing political change more broadly. We argue that the political implications of African urbanization are contingent on local conditions and experiences; there are no deterministic associations between urbanization and political change. To better understand the mechanisms linking urbanization to politics, we argue that a place-based approach is needed. We illustrate this by reviewing and highlighting how urbanization may affect (i) the nature and balance of citizen preferences; (ii) the composition, interests, and influence of elite actors; (iii) forms of political mobilization; (iv) shifting gender roles; (v) the role of civil society in political processes; and (vi) the likelihood and manifestations of contentious collective action. We conclude with a discussion of directions for further research.","PeriodicalId":7508,"journal":{"name":"African Affairs","volume":"9 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-07-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"134983663","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"社会学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Abstract After violence ends, former conflict parties and their civilian supporters often disagree about the origins and causes of the conflict. Post-conflict states vary in how they deal with these competing accounts of the past, ranging from selective remembering to state-backed forgetting. However, conflict narratives that are excluded from the public sphere are not necessarily forgotten and may be passed on between generations within families, social networks, and communities. These unofficial and often biased accounts can threaten the stability of post-conflict societies when appropriated by political actors who seek to challenge hegemonic memory practices and/or the legitimacy of the state—a process that we define as memory mobilization. In this paper, we argue that memory mobilization is particularly likely to occur when (1) unofficial conflict narratives persist among certain groups and sections of society, and are transferred from one generation to the next; and (2) regime opponents and/or other political actors have sufficient political and public space for contestation. To evaluate our argument, we examine these issues in the context of post-conflict Côte d’Ivoire. Based on 905 secondary school student essays, we show that competing accounts are reproduced among young Ivoirians and that these could potentially threaten the country’s future stability, if misappropriated.
{"title":"Memory mobilization and Postconflict Stability in Côte D’ivoire: Analysing the transmission of conflict narratives among Ivoirian Youth","authors":"Line Kuppens, Arnim Langer","doi":"10.1093/afraf/adad022","DOIUrl":"https://doi.org/10.1093/afraf/adad022","url":null,"abstract":"Abstract After violence ends, former conflict parties and their civilian supporters often disagree about the origins and causes of the conflict. Post-conflict states vary in how they deal with these competing accounts of the past, ranging from selective remembering to state-backed forgetting. However, conflict narratives that are excluded from the public sphere are not necessarily forgotten and may be passed on between generations within families, social networks, and communities. These unofficial and often biased accounts can threaten the stability of post-conflict societies when appropriated by political actors who seek to challenge hegemonic memory practices and/or the legitimacy of the state—a process that we define as memory mobilization. In this paper, we argue that memory mobilization is particularly likely to occur when (1) unofficial conflict narratives persist among certain groups and sections of society, and are transferred from one generation to the next; and (2) regime opponents and/or other political actors have sufficient political and public space for contestation. To evaluate our argument, we examine these issues in the context of post-conflict Côte d’Ivoire. Based on 905 secondary school student essays, we show that competing accounts are reproduced among young Ivoirians and that these could potentially threaten the country’s future stability, if misappropriated.","PeriodicalId":7508,"journal":{"name":"African Affairs","volume":"4 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-07-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"135805362","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"社会学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
How do national identities matter in global health? Our paper addresses this question through a study of Kenya’s vaccine diplomacy during the Covid-19 pandemic. It combines critical perspectives, challenging the neglect of African agency in international relations (IR), with constructivist approaches highlighting the importance of discourse in the exercise of agency. The insight that identity is an important resource in the realization of foreign policy goals is confirmed by our review of interventions by senior Kenyan leaders, as well as ministries and official bodies, concerned with vaccine procurement during the pandemic. Moreover, this material shows that identity is not pre-given, but rather performed in discourse, being adapted and renewed in speeches, briefings, policy documents, and so on. Identities are plural, not singular, drawing on historic and cultural resources proper to individual states. This allows us to link the range of identities performed during the Covid-19 pandemic to earlier moments in Kenya’s diplomatic history, noting the continued pertinence of its image, variously, as ‘an island of stability’, ‘a good global health citizen’, ‘a member of the pan-African community of states’, and ‘an active contributor to IR’.
{"title":"National Identities in Global Health: Kenya’s Vaccine Diplomacy During the Covid-19 Pandemic","authors":"John Harrington, D. Ngira","doi":"10.1093/afraf/adad015","DOIUrl":"https://doi.org/10.1093/afraf/adad015","url":null,"abstract":"\u0000 How do national identities matter in global health? Our paper addresses this question through a study of Kenya’s vaccine diplomacy during the Covid-19 pandemic. It combines critical perspectives, challenging the neglect of African agency in international relations (IR), with constructivist approaches highlighting the importance of discourse in the exercise of agency. The insight that identity is an important resource in the realization of foreign policy goals is confirmed by our review of interventions by senior Kenyan leaders, as well as ministries and official bodies, concerned with vaccine procurement during the pandemic. Moreover, this material shows that identity is not pre-given, but rather performed in discourse, being adapted and renewed in speeches, briefings, policy documents, and so on. Identities are plural, not singular, drawing on historic and cultural resources proper to individual states. This allows us to link the range of identities performed during the Covid-19 pandemic to earlier moments in Kenya’s diplomatic history, noting the continued pertinence of its image, variously, as ‘an island of stability’, ‘a good global health citizen’, ‘a member of the pan-African community of states’, and ‘an active contributor to IR’.","PeriodicalId":7508,"journal":{"name":"African Affairs","volume":" ","pages":""},"PeriodicalIF":2.8,"publicationDate":"2023-06-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"45572938","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"社会学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
The Yoruba: from Prehistory to the Present by Aribidesi Usman and Toyin Falola (2019) and The Yoruba: A New History (2020) by Akinwunmi Ogundiran are two monumental contributions to the history of the Yoruba written in the twenty-first century. In addition to earlier works on the Yoruba by scholars such as Samuel Johnson (1921) and Akin Akinjogbin (2002), amongst others, these two books, published a year apart, both provide unique perspectives on the Yoruba in the long durée drawing on continued archaeological work done in the area. Nevertheless, these are two very different books. Aribidesi and Falola’s work explores the development of Yoruba as a cultural complex within a cultural-historical framework. Ogundiran’s work examines the different processes that shape Yoruba lifeways and communal practices up to the 1840s with relevance to the present. Here, the focus is on the development of lived experiences of the group, analysed with a more post-processual theoretical outlook.
{"title":"Book Review","authors":"Sibanengi Ncube","doi":"10.1093/afraf/adad018","DOIUrl":"https://doi.org/10.1093/afraf/adad018","url":null,"abstract":"The Yoruba: from Prehistory to the Present by Aribidesi Usman and Toyin Falola (2019) and The Yoruba: A New History (2020) by Akinwunmi Ogundiran are two monumental contributions to the history of the Yoruba written in the twenty-first century. In addition to earlier works on the Yoruba by scholars such as Samuel Johnson (1921) and Akin Akinjogbin (2002), amongst others, these two books, published a year apart, both provide unique perspectives on the Yoruba in the long durée drawing on continued archaeological work done in the area. Nevertheless, these are two very different books. Aribidesi and Falola’s work explores the development of Yoruba as a cultural complex within a cultural-historical framework. Ogundiran’s work examines the different processes that shape Yoruba lifeways and communal practices up to the 1840s with relevance to the present. Here, the focus is on the development of lived experiences of the group, analysed with a more post-processual theoretical outlook.","PeriodicalId":7508,"journal":{"name":"African Affairs","volume":"3 3","pages":""},"PeriodicalIF":2.8,"publicationDate":"2023-06-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"41259677","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"社会学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Reading Ethnography" presents a model for analyzing and evaluating ethnographic arguments. Through this book
《阅读民族志》提供了一个分析和评价民族志论点的模型。通过这本书
{"title":"Book Review","authors":"J. Lar","doi":"10.1093/afraf/adad017","DOIUrl":"https://doi.org/10.1093/afraf/adad017","url":null,"abstract":"Reading Ethnography\" presents a model for analyzing and evaluating ethnographic arguments. Through this book","PeriodicalId":7508,"journal":{"name":"African Affairs","volume":" ","pages":""},"PeriodicalIF":2.8,"publicationDate":"2023-06-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"41348064","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"社会学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
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