共查询到20条相似文献，搜索用时 62 毫秒
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张敏 《广东广播电视大学学报》2003,12(2):75-77
本文研究了双模压缩真空态1ξ〉=1/coshr sum from n=0 to(-e~(iθ)tanhr)~n 1n,n)的K次方H压缩效应。数值计算的结果表明:对于双模压缩真空态,光场存在着K次方H压缩效应(K=1,2,3,4,5,Λ);但是,随着方次K的升高,K次方H压缩效应减弱。 相似文献
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由奇、偶相干态光场组成的第Ⅰ种四态叠加多模叠加态光场的等阶N次方H压缩 总被引：1，自引：0，他引：1
根据量子力学中的线性叠加原理 ,构造了由多模奇、偶相干态光场所组成的第 种四态叠加多模叠加态光场 |Ψ (4)o,e, 〉q.利用多模压缩态理论 ,研究了态|Ψ (4)o,e, 〉q的等阶 N次方 H压缩特性 .结果发现 :1)当腔模总数 q与压缩阶数 N的乘积 q . N为偶数时 ,态 |Ψ (4)o,e, 〉q 恒处于等阶 N - H最小测不准态 ;2 )当 q . N为奇数时 ,则在各纵模初始相位之和 ∑qj=1φj、态间相位之差 (θe -θo)、各模平均光子数 R2j 以及四态叠加的几率幅 re、ro等取不同定值的条件下 ,态 |Ψ(4)o,e, 〉q可呈现出以下几种效应 :1等阶 N - H最小测不准态 ;2等阶 N次方 H压缩效应 ;3“半相干态”效应 ;4“半相干—半压缩态”效应 (即在一定条件下 ,态 |Ψ(4)o,e, 〉q的两个正交分量中的一个分量呈现等阶 N次方 H压缩效应 ,另一个分量处于等阶 N - H最小测不准态 ) ;5“完全的等阶 N次方 H压缩”效应 (即在一定条件下 ,态 |Ψ (4)o,e, 〉q 的两个正交分量可同时呈现出等阶 N次方 H压缩效应 ,简称为“完全压缩态”效应 ) . 相似文献
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江俊勤 《广东教育学院学报》2005,25(3):41-44
研究了对相干态|ζ>=A0n=∞∑0nnζ!|n,n>的非线性高阶压缩效应.结果表明:对于对相干态,光场存在着等阶N(=2,3,4,5,…)次方Y压缩效应,但不存在着等阶N次方H压缩效应,对相干态是N-H最小不确定态. 相似文献
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根据量子力学中的线性叠加原理，构造了由多模真空态|{Oj}&;gt;q和多模虚相干态|{ihj}&;gt;q这两者的线性叠加所组成的第IX类两态加多模叠加态光场|Ψ9^(2)&;gt;q利用多模压缩态理论，对态|Ψ9^(2)&;gt;q的广义非线性N次方Y压缩特性进行了详细研究．结果发现：(1)、无论压缩次数N取奇还是取偶，只要各模的初始相位φj(j=1,2,3,…{，q）和态间的初始相位差(θpq^(1)-θoq^(o))分别满足一定的量子优化条件，态|Ψ9^(2)&;gt;q的第一和第二这两个正交分量总可分别呈现出周期性变化的任意奇数次和任意偶数次的广义非线性N次方Y压缩效应；(2)、本文所构造的态|Ψ9^(2)&;gt;q与文献[11]构造的态|Ψ9^(2)&;gt;q，两者在一定条件下可分别呈现出“N次方Y相似压缩”和“N次方Y压缩简并”现象。 相似文献
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两不同偶相干态组成的第Ⅱ种四态叠加多模叠加态光场的等阶N次方H压缩 总被引：1，自引：1，他引：0
构造了由两不同偶相干态组成的第 种四态叠加多模叠加态光场|Ψ (4)e , 〉q,利用新近建立的多模压缩态理论 ,详细研究了态 |Ψ (4)e , 〉q 的广义非线性等阶 N次方 H压缩特性 ,结果发现 :1)当 q .N =2 p(p =1,2 ,3,… )、∑qj =1φj =± kπN(k =0 ,1,2 ,… )时 ,态 |Ψ(4)e , 〉q恒处于等阶 N— H最小测不准态 ;2 )当 q.N为偶数且 q .N =4m - 2 (m =1,2 ,3,… )时 ,在不同的限定条件下 ,态 |Ψ (4)e , 〉q可分别呈现出以下状态 :(1)第一正交分量处于等阶 N— H最小测不准态的同时 ,第二正交分量既不处于等阶 N— H最小测不准态 ,也不呈现等阶 N次方 H压缩效应而使态 |Ψ(4)e , 〉q 呈现“半相干态”效应 ;(2 )第一正交分量呈现等阶 N次方 H压缩效应 ,其压缩情况与第 种四态叠加多模叠加态光场 |Ψ(4)e , 〉q 的情形完全相同 ,出现“部分压缩简并”现象 ;(3)当 q.N为奇数时 ,在一定限定条件下 ,态 |Ψ (4)e , 〉q可处于等阶 N— H最小测不准态 ;在另外限定条件下 ,态 |Ψ(4)e , 〉q 的两个正交分量可分别呈现等阶 N次方 H压缩效应 相似文献
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本利用多模压缩态理论研究了第I种非对称两态叠加多模叠加态光场|ψI^（ab）＞q的不等次幂Nj次方H压缩特性。结果发现：当各模压缩幂次数之和为奇数时，态|ψI^（ab）＞q的第一或第二正交分量可分别呈现出周期性变化的不等次幂Nj次方H压缩效应。 相似文献
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第Ⅸ类两态叠加多模叠加态光场的广义非线性N次方Y压缩特性研究 总被引：1，自引：0，他引：1
根据量子力学中的线性叠加原理,构造了由多模真空态|{Oj}〉q和多模虚相干态|{ihj}〉q这两者的线性叠加所组成的第Ⅸ类两态加多模叠加态光场|ψ(2)9〉q.利用多模压缩态理论,对态|ψ(2)9〉q的广义非线性N次方Y压缩特性进行了详细研究.结果发现(1)、无论压缩次数N取奇还是取偶,只要各模的初始相位ψj(j=1,2,3,…,q)和态间的初始相位差(θ(I)pq-θ(o)oq))分别满足一定的量子优化条件,态|ψ(2)9〉q的第一和第二这两个正交分量总可分别呈现出周期性变化的任意奇数次和任意偶数次的广义非线性N次方Y压缩效应;(2)、本文所构造的态|ψ(2)9〉q与文献[11]构造的态|ψ(2)5〉q,两者在一定条件下可分别呈现出"N次方Y相似压缩"和"N次方Y压缩简并"现象. 相似文献
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薛红 《西安文理学院学报》2005,8(1):55-58
利用多模压缩态理论，详细研究了一种强度不等的非对称两态叠加多模叠加态光场的等幂次N次方H压缩特性．结果发现：当腔模总数q与压缩次数N的乘积分别满足一定的条件，则(1)态的第一和第二这两个正交相位分量总可呈现出周期性变化的等幂次N次方H压缩效应；(2)态可呈现出“等幂次N次方H压缩简并”现象． 相似文献
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根据量子力学中的线性叠加原理，构造了多模奇相干态和多模虚偶相干 态组成的第Ⅳ种态叠加多模叠加态光场|ψ^(4)oe,Ⅳ&;gt;q.利用多模压缩态理论研究了态|ψ^(4)oe,Ⅳ&;gt;q，Ⅳ&;gt;q3的等阶N次方H压缩特性，结果发现：（1）当压缩阶数N与腔模总数q之积qN为偶数时：a．若qN=4m(m=1，2，3，…）时，态|ψ^(4)oe,Ⅳ&;gt;q处于等阶N－H最小刻测不准态。b．若qN=4m′+2(m′＝0，1，2，…），且q/∑／j＝1Nψj=&;#177;kψπ（或&;#177;kψπ＋π／2）（kψ＝0，1，2，…）时，态|ψ^(4)oe,Ⅳ&;gt;q呈现“半相干态”效应，2）当qN=2p′＋1（p′＝0，1，2，…）时，态|ψ^(4)oe,Ⅳ&;gt;q可呈现以下三种状态：a．当q/∑／j＝1Nψj=1=&;#177;kψπ(kψ=0，1，2，…）时，第一正交分量可呈现等阶N次方H压缩效应，b、当q/∑／j＝1Nψj＝&;#177;kψπ＋π／2（kψ＝0，1，2，…）时，第二正交分量可呈现等阶N次方H压缩效应；c.“半相干态”效应。 相似文献
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《职教通讯(江苏技术师范学院学报)》2005,11(4)
利用多模压缩态理论,研究了由多模复共轭相干态|{zj(a)*}〉q=|{Rj(a)exp(-iψj)}〉q和多模虚相干态|{±izj(b)*}〉q=|{±iRj(b)exp(-iψj)}〉q的线性叠加所组成的两类非对称多模量子叠加态|ψ±(2)〉q在各个模的压缩阶数全为偶数即Nj=2pj=1,2,3,……q,pj=1,2,3,……)的条件下的偶数次不等幂次Nj次方Y压缩效应.结果发现:如果各个模初始位相ψj以及态|{zj(a)*}〉q和|{±izj(b)*}〉q之间的初始相位差θpq(R)-θnq(I)与各个对应模的振幅Rj(a)和Rj(b)的乘积的总和q∑j=1Rj(a)Rj(b)所组成的混合初始相位[(θpq[R]-θnq(I))-+q∑j=1Rj(a)Rj(b)]分别满足一定的条件时,态|ψ±(2)〉q总可呈现出周期变化的偶数次不等幂次Nj次方Y压缩效应.当pj均为奇数时可获得较大的压缩深度. 相似文献
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《海外英语》2007,(5):10-11
Many college freshmen arrive woefully unprepared to do college work, and as disadvantaged populations continue to grow, the share of the American work force that has made it through college is expected to plummet. Many experts blame that educational failure not just on high schools but also on colleges. School & College, a special report by The Chronicle, looks at efforts to fix the system. What reforms would better prepare students for college? What should schools and colleges be doing differently? How should state and federal officials help? 相似文献
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《海外英语》2007,(4):36
There are numbers of crossroads on our long and unpredictable life journey where we totally have no idea about which direction to choose. No matter what our decision is, we should not turn back, but face the music and go ahead instead. I am this kind of girl who always does try without regretting, one example is how I dealt with my love. 相似文献
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Migration occurs behind a variety of reasons and has a great effect on the whole world. People may migrate in order to improve their economic situation, or in order to escape civil strife, persecution, and environmental disasters. The impact of migration is complex, bringing both benefits anddisadvantages. This paper briefly talks about the causes of migration, the allocation of benefits, and the ways in which individual countries and the international community deal with this important subject. 相似文献
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Sister Carrie is one of the most controversial characters in American literature.Thought as a "fallen woman" firstly,she was defined as a "new woman" by some critics later. However, by digging into the motivaton behind the whole process of Carrie's "success", the relationship between Carrie and her creator (the author), the social conditions of then American, it can be found that Carrie has never been free-standing on her thought and she has never found her real-sdf even after becoming a famous actress. In a society dominated by mass consumerism Carrie is only an adherent of her own desires. She also is a representative of all those country girls flooded into cities, a symbol and a sacrifice of the urbanization of America in a time countryside was overcome by cities. 相似文献
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RUZBEHANI Mohsen 《重庆大学学报(英文版)》2004,3(1):20-25
1.IntroductionOne-cyclecontrolmethod,whichwasproposedaboutonedecadeago[1],hasbecomeanattractivemethodinspecialfieldssuchaspowerfactorcorrection[2-6],switchingamplifiers[7,8],etc.Themainideaofthiscontrollerisbasedonintegrationofdiodevoltageinone-cycleandforcesittobeexactlyequaltothereferencevalue.Themainadvantageofthiscontrollerisitsrealtimeabilitytorejectthevariationofinputvoltage[1].Despitethisgreatability,ithasnogoodperformancesinrejectingofloaddisturbanceandfollowingreferencecommands.Espec… 相似文献
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唐芳 《读与写:教育教学刊》2008,5(6)
During interview with English majors, it was found that a majority of students expressed disappointment with their experience of English literature classes. Students' dislike of learning English literature appears to be the major problem of teaching English literature in China. Reader response approach is a good way to solve this problem. In this paper, I explain the rationale behind the reader response approach, such as its origin, definition, features, assumptions, and strategies. Then I illustrate how reader response approach works as a teaching strategy by presenting several teaching models. At last I evaluate its usefuiness for teachers and present the advantages of reader response approach in Chinese context. 相似文献