August 2020
Beginner to intermediate
332 pages
8h 16m
Japanese
book
動かして学ぶ量子コンピュータプログラミング ―シミュレータとサンプルコードで理解する基本アルゴリズム
by Eric R. Johnston, Nic Harrigan, Mercedes Gimeno-Segovia, 北野 章, 丸山 耕司
Content preview from 動かして学ぶ量子コンピュータプログラミング ―シミュレータとサンプルコードで理解する基本アルゴリズム
Become an O’Reilly member and get unlimited access to this title plus top books and audiobooks from O’Reilly and nearly 200 top publishers, thousands of courses curated by job role, 150+ live events each month,
O’Reilly covers everything we've got, with content to help us build a world-class technology community, upgrade the capabilities and competencies of our teams, and improve overall team performance as well as their engagement.I wanted to learn C and C++, but it didn't click for me until I picked up an O'Reilly book. When I went on the O’Reilly platform, I was astonished to find all the books there, plus live events and sandboxes so you could play around with the technology.I’ve been on the O’Reilly platform for more than eight years. I use a couple of learning platforms, but I'm on O'Reilly more than anybody else. When you're there, you start learning. I'm never disappointed.I'm always learning. So when I got on to O'Reilly, I was like a kid in a candy store. There are playlists. There are answers. There's on-demand training. It's worth its weight in gold, in terms of what it allows me to do.
8.7
QPU
の内部
163
8.7.1
感覚を養う
QPU
演算で固有位相を求めることは非常に簡単なことに思えるかもしれません。
phase_est()
は
注目する
QPU
演算とその固有状態の
1
つ（またはそれ以上）にアクセスできるので、図8-7に示すよう
に、固有状態に対する
QPU
演算に適用してみましょう。
グローバルな固有位相を
持った固有状態
固有状態
図8-7
固有状態と固有位相の定義から、位相推定のこの単純なプログラムを使うと、入力した固有状態と
同じ状態が出力レジスタで得られます。ただし、出力レジスタにはグローバルな位相として固有位相を
乗じます。この方法で出力レジスタの固有位相
θ
が現れますが、グローバルな位相を読み出すことはで
きません。この単純な方法では、
QPU
レジスタの位相に隠された、私たちの望む情報を取り出すとい
う課題を達成することはできません。
図8-7を微調整し、レジスタの読み出し可能な特性の中から目的の固有位相を獲得する方法が必要
です。現在使えるツールの中では、
QFT
が役に立ちそうです。
QFT
は周期的な位相差を、読み出し可能な振幅に変換することを思い出してください。したがって、
出力レジスタの相対位相を固有位相による振動数に従って周期的に変化させる方法を見つけられれば
ひと安心です。こうなれば、逆
QFT
を単純に応用することで固有位相を読み出すことができます。
2
つの固有位相の角度を例とした演算の流れを図8-8に図示し、ここでの課題を明確にします。
固有位相
θ
＝
Become an O’Reilly member and get unlimited access to this title plus top books and audiobooks from O’Reilly and nearly 200 top publishers, thousands of courses curated by job role, 150+ live events each month,
and much more.
Read now
Unlock full access
More than 5,000 organizations count on O’Reilly
O’Reilly covers everything we've got, with content to help us build a world-class technology community, upgrade the capabilities and competencies of our teams, and improve overall team performance as well as their engagement.Julian F.
I wanted to learn C and C++, but it didn't click for me until I picked up an O'Reilly book. When I went on the O’Reilly platform, I was astonished to find all the books there, plus live events and sandboxes so you could play around with the technology.Addison B.
I’ve been on the O’Reilly platform for more than eight years. I use a couple of learning platforms, but I'm on O'Reilly more than anybody else. When you're there, you start learning. I'm never disappointed.Amir M.
I'm always learning. So when I got on to O'Reilly, I was like a kid in a candy store. There are playlists. There are answers. There's on-demand training. It's worth its weight in gold, in terms of what it allows me to do.