近年來，由於量子資訊科學的研究迅速發展，近代密碼學的安全性已開始遭受質疑。舉例來說，近代密碼學中的非對稱式金鑰密碼系統，其安全性是建立於目前電腦技術難以解決的數學難題上。然而，在量子電腦的研究中，已經提出有效率的演算法，使得其數學難題可以在線性時間內破解。因此，要如何在量子電腦的環境中，設計出安全且新穎的量子密碼技術，在這幾年來也成為密碼學家的主要研究方向。
在量子密碼學中，如何適當地去運用量子的糾纏特性是建構量子密碼技術的核心技術。許多量子密碼技術，如：量子金鑰分配協定、量子秘密分享協定、量子直接通訊、量子模糊傳送等，均應用糾纏態量子的特性來達成。
量子秘密分享協定(Quantum Secret Sharing)為量子密碼學上一重要的研究方向。量子秘密分享協定允許資訊擁有者利用量子的特性將次金鑰安全地分散給n個成員，而這n個成員必須一起合作，才能還原擁有者的原始資訊。近年來，已有許多量子秘密分享協定被發表出來。這些機制均是植基於單光子、EPR糾纏態量子或是GHZ糾纏態量子。
在最近的研究中，許多新穎的糾纏態量子陸續被發現，其中包含了W糾纏態量子、GHZ-like糾纏態量子與Cluster糾纏態量子等。這些新發現的糾纏態量子具有一些新奇有趣的物理特性。然而，目前卻還沒有文獻利用這些糾纏態量子來建構量子秘密分享機制。因此，本論文利用這些糾纏態量子的物理特性來建構多個量子秘密分享協定並且提供更佳的效率。

Nowadays, the security of modern cryptography cannot always be guaranteed because of the rapid development of quantum information science. For example, the security of public key cryptosystems is based on mathematical problems that are difficult to solve even by using modern computer techniques. However, some efficient algorithms have been proposed to solve these mathematical problems in polynomial time by using quantum computer techniques. Therefore, in this decade, the design of secure and novel quantum cryptographic schemes has become a major topic of research for cryptographers.
The core technique to construct quantum cryptographic schemes is to appropriately utilize quantum entanglement. Several types of quantum cryptographic schemes, such as quantum key distribution protocol (QKDP), quantum secret sharing (QSS), quantum secure direct communication (QDC), and quantum oblivious transfers (QOT), are achieved by using the property of entangled quantum states.
QSS is an important branch of quantum cryptography. A QSS scheme allows a secret holder to securely distribute a secret to n members on the basis of the property of qubit; further, all of the n members must collaborate to recover the secret of the owner. Several QSS schemes have been proposed in the recent years. The quantum states that are applied in these QSS schemes are single photons, EPR pairs, or GHZ states.
In the latest studies, some novel entangled quantum states have been discovered, in-cluding the W state, GHZ-like state, and cluster state. These entangled states have some new interesting physical properties. However, the existing literature does not have any mention of a QSS scheme that applies these novel entangled quantum states. Therefore, in this thesis, we propose several QSS schemes by using the property of these novel entan-gled states; these schemes are more efficient than the existing GHZ-class-based QSS schemes.

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